Know the History and reduce the Risk

Compiled by Ms Carin Brent (Dipl OH US, EF UWC)

MDB006-MD617-0058-7-2019

Factors to consider in history taking History taking is a skill that requires practice. Patients respond in different ways to similar lines of questioning, and it may be necessary to modify questioning style or to ask the same question several times but in different ways in order to optimise the information obtained. The medical and dental professions are often poor listeners and interject at the earliest opportunity. Although practitioners are all familiar with patients who present their ‘life story’ following the practitioner’s opening question, much important information may be lost by frequent interruptions or curtailing the patient’s answers. Other reasons for poor history giving by the patient may include fear or apprehension about treatment, anxiety around hospital-type situations, the so-called `white coat syndrome’. A perceived lack of confidentiality or an unwillingness to disclose information in front of a parent or other family member may prevent a patient from talking freely. Some patients may have a fear or embarrassment about their condition or what the clinician might say. The patient may misguidedly think that the requested information does not matter or is no business of the clinician. In such cases, the practitioner needs to be persistent in obtaining the information and reassure and explain to the patient why the information is being requested. The clinician may need to take the case history in a more private situation with only a member of staff present to chaperone.[1]

This is an abstract of an article, Essentials of Medical History-Taking in the Dental Patient by Dr Mark Greenwood published in the Dental Update in May 2015:[2]

All dental practitioners are familiar with the main components of the history taking process. The purpose of this paper is to revise those areas and add some context to some of the more important aspects and provide updates where appropriate.

The main components of a patient history Presenting complaint The presenting complaint may best be expressed in the patient’s own words. The information presented can then be summarized by the clinician.

History of presenting complaint A chronological approach should be used. As a minimum, the history of a presenting complaint should include the following:

When the condition/problem first started;

The overall duration and progression of the condition, including whether it is episodic or constant;

The nature and timing of any symptoms (see below);

Details of any systemic signs or symptoms (such as fever);

The success or otherwise of previous treatments;

Previous practitioners who have been consulted regarding the same or related condition(s).

In dental practice, the presenting complaint is often pain. A generic scheme of questions to assess the nature and severity of a patient’s pain is shown as follows:

o Site of pain − it is useful to ask the patient to point with one finger to where the pain is worst;

o Character, eg sharp, ache, throbbing; o Ask about severity − on a scale of 1−10, 10 being the most severe − how bad is it?; o Does the pain radiate anywhere else?; o Timing − was the onset sudden or gradual? − how long has the pain been present? − is it

continuous or intermittent? − worse at any particular time of day?; o What makes the pain better or worse (including the use and type of medication); o Is the patient aware of any relevant preceding event, including previous similar episodes?; o Any associated symptoms, for example bad taste? Past medical history Generic questioning regarding major systems such as the cardiovascular or respiratory systems is often the way practitioners start obtaining a medical history. Questioning should then focus on specific disorders,1 such as asthma or other respiratory disorders, diabetes mellitus, epilepsy, hypertension or other cardiovascular problems (stroke, myocardial infarction, angina), hepatitis or jaundice. Positive responses should be followed-up by an assessment of the severity of the disorder, treatments used and their efficacy. Previous problems with the arrest of haemorrhage are worth specific enquiry. The past medical history is an essential component of risk assessment for the likelihood of a patient experiencing a medical emergency. The Resuscitation Council (UK) provide authoritative and up-to-date advice regarding the management of medical emergencies in dentistry.2 It is essential to ask about any known allergies and, if a positive response is obtained, to enquire about the nature of such an allergy

Specific situations and management considerations Pregnancy Pregnant patients require special considerations in their management. Some of the more important ones are summarized as:

The second trimester is the optimum time for treatment; Best where possible to avoid prescribing drugs; If prescriptions are necessary, check in the British National Formulary (BNF); Drugs taken by mother while breast-feeding can be transferred in some cases to breast

milk. Local anaesthetic containing adrenaline is acceptable; Patients who faint or feel faint should be treated in the left lateral position to avoid

pressure on the inferior vena cava and minimize risk of supine hypotension syndrome;

Intravenous sedation must be avoided in the first trimester and the last month of the third trimester and ideally best avoided completely;

Nitrous oxide can interfere with vitamin B12 and folate metabolism − should not be used in first trimester − if used, exposure should be less than 30 minutes, use 50% oxygen and avoid repeated exposure.

Sickle cell anaemia Sickle cell anaemia is an inherited haemoglobinopathy found in individuals of African, Asian and Mediterranean origin. In situations of lowered oxygen tension the abnormal haemoglobin results in red blood cells becoming sickle-shaped, leading to increased blood viscosity and capillary thrombosis. It can present either as a sickle cell trait (heterozygous) or sickle cell anaemia itself (homozygous).

Leukaemias Liaison with a haematologist is important due to the potential difficulty in controlling post-operative bleeding and increased risk of infection.

Steroid treatment Patients taking long-term corticosteroid therapy will normally carry a steroid treatment card giving details of the drug being used, its dosage and duration of treatment. If steroid supplementation is required prior to treatment, acute adrenal insufficiency can be prevented. An increased dose of corticosteroid should be administered prior to treatment in such cases. Simple dental extractions and restorative dental procedures are not usually a cause for concern,3 but surgical extractions, the placement of dental implants or treatment under general anaesthesia are a potential risk.

Medications and drugs All medications or drugs that the patient may be taking should be included.4 This should include ‘recreational’ drugs and homeopathic or other over-the–counter preparations. In addition, it is pertinent to ask about inhaled or topical medicines as many patients do not consider these as ‘drugs’. Concurrent drug therapy can impact upon orofacial signs and symptoms, the safe provision of dental treatment and the use of other medications. Well known examples of drugs that are highly relevant in the context of dental treatment include anticoagulants, such as warfarin and dabigatran and bisphosphonates. Osteonecrosis is a recognized complication of bisphosphonate treatment.5 The condition is defined as the presence of exposed bone for longer than 8 weeks in the absence of radiotherapy treatment but in a patient who is using bisphosphonates. It is diagnosed clinically but local malignancy must be excluded.6 The bisphosphonates are a group of drugs which include alendronic acid and risedronate sodium. These drugs become adsorbed onto hydroxyapatite crystals thereby slowing their rate of dissolution and growth. Such drugs have been used in the management of osteoporosis in postmenopausal women, patients with bony metastases and the hypercalcaemia of malignancy. Clearly, it is preferable to avoid dental extractions if possible in patients taking bisphosphonates. Local guidelines should be consulted when extractions are unavoidable in these patients. Established cases of osteonecrosis require analgesia, and long-term antiobiotic therapy and topical antiseptic therapy if infected. Occasionally, careful local debridement may be indicated to remove limited bony sequestra.7 Risk factors that increase the possibility of osteonecrosis developing include local infection, steroid use, trauma, chemotherapy and periodontal disease. As well as effects on bone, it is thought that bisphosphonates might have toxic effects on soft tissues around an extraction site, impairing the function of vascular and epithelial cells.

’Recreational’ drugs The use of drugs of abuse is common and dentists should have a working knowledge of the implications for patients who say that they are using these. Cannabis has a sympathomimetic action and in theory could exacerbate the systemic effects of adrenaline in dental local anaesthetics. Heroin and methadone are opioid drugs, the latter being used in rehabilitation programmes. Oral methadone has a high sugar content that can cause rampant caries. Heroin can cause thrombocytopaenia (deficiency of platelets in the blood. This causes bleeding into the tissue, bruising, and slow blood clotting after injury). Some of those addicted to heroin have a low threshold for pain. The drug also interacts with preparations that dentists may prescribe.8 The absorption of paracetamol and orally administered diazepam is delayed and reduced due to delayed gastric emptying. Carbamazepine reduces serum methadone levels and methadone increases the effects of tricyclic antidepressants.

Amphetamines and ecstasy may produce thrombocytopaenia. Concomitant use with monoaminoxidase inhibitors (any of a group of antidepressant drugs which inhibit the activity of monoamine oxidase so allowing accumulation of serotonin and noradrenaline in the brain) and tricyclic antidepressants can precipitate a hypertensive crisis.

Patients who abuse cocaine are subject to increased risk of the effects of ischaemia (an inadequate blood supply to an organ or part of the body, especially the heart muscles) leading to loss of tissue. Testing the ‘quality’ of the drug by rubbing on the oral mucosa to test depth of anaesthesia may lead to loss of gingivae and alveolar bone. An increased incidence of dental caries may be seen if cocaine is bulked out with carbohydrates. As with heroin, thrombocytopaenia may be seen and, like cannabis, cocaine has a sympathomimetic action.

LSD (lysergic acid diethylamide) is an hallucinogenic drug. Such drugs increase the incidence of bruxism and patients taking it may present with TMJ dysfunction. Dentists should be aware that stressful situations may cause flashbacks and panic attacks in these patients.

A reduction in the dose of adrenaline containing local anaesthetics is recommended in those who chronically abuse solvents as such agents can sensitize the myocardium to the actions of the catecholamine. Solvent abuse also increases the risk of convulsions and status epilepticus (a dangerous condition in which epileptic fits follow one another without recovery of consciousness between them) may occur.

Some patients may abuse anabolic steroids and performance enhancers, which may precipitate increased carbohydrate consumption with its inevitable effects on the dentition. The systemic effects of adrenaline in dental local anaesthetics can be exacerbated by the sympathomimetic effects of certain anabolic steroid drugs. As with many other illicit drugs, anabolic steroids may interfere with blood clotting.

Complementary therapies Complementary therapies are often used by patients. It is important to remember possible interactions with prescription drugs, some of which may be prescribed by dental practitioners. Some of the more common interactions are shown below:

HERB CONVENTIONAL DRUG POTENTIAL PROBLEM

St John’s wort

Monoamine oxidase inhibitor and Serotonin reuptake inhibitor Antidepressants Iron

Mechanism of herbal effect uncertain. Insufficient evidence of safety with concomitant use − therefore not advised May limit iron absorption

Karela, ginseng Insulin, sulphonylureas, biguanides

Altered glucose concentrations

Feverfew, garlic, ginseng, ginger

Warfarin Altered prothrombin time/INR (The time in which prothrombin changes to thrombin to stop the bleeding.)

Echinacea used for >8 weeks Anabolic steroids, methotrexate, Amiodarone, ketoconazole

Hepatotoxicity

Feverfew Non-steroidal anti-inflammatory drugs

Inhibition of herbal effect

Ginseng Oestrogens, corticosteroids Additive effects Evening primrose oil Anticonvulsants Lowered seizure threshold Kava Benzodiazepines Additive sedative effects, coma Echinacea, zinc (immunostimulants)

Immunosuppressants (such as corticosteroids, ciclosporin)

Antagonistic effects

Past dental history The past dental history assumes different forms, depending on the patient’s previous exposure to dental treatment. It is clearly relevant to find out whether a patient is a regular attender and of their previous experience of dental treatment and its nature. The previous use of local anaesthetic agents and any associated problems can be checked. If not covered by the previous history, adverse events, such as post-extraction haemorrhage, may be highlighted at this point. Cardiovascular system

A differential diagnosis of chest pain (bearing in mind other potential causes) includes: – Angina; – Myocardial infarction; –Oesophageal reflux; –Musculoskeletal; –Pleuritic (for example pulmonary embolism); –Hyperventilation; –Referred pain from the abdomen.

Does the chest pain occur at rest or after exertion − how much exertion?; Dyspnoea (remember potential respiratory causes either co-existing or in isolation); Does breathlessness occur at rest/on exertion?; Paroxysmal nocturnal dyspnoea (waking from sleep feeling breathless) or

orthopnoea (breathlessness on lying flat); Palpitations; Prosthetic/replacement heart valves; History of rheumatic fever and/or infective endocarditis;

Claudication pains (pain and/or cramping in the lower leg due to inadequate blood flow to the muscles) and what is required to precipitate them.

Cardiovascular disorders and potential management implications are summarized below:

Medical Problem Implications for Management

Valve replacement, structural cardiac Defect

SA guidelines not clear. Consult with patient’s physician

Myocardial infarction No elective dental treatment for 3 months after an MI. Ideally no general anaesthetic for the first 6 months.

Angina Ensure availability of emergency drugs and oxygen. Enquire about frequency of attacks, their precipitation and effectiveness of GTN.

Hypertention In oral surgical cases if more than 160/100 mmHg, consider postponing until better control. In acute situations IV sedation may be helpful.

Respiratory system Breathlessness/wheeziness; The presence or otherwise of a cough, its duration and whether productive or not;

Haemoptysis (coughing up blood); History of known respiratory disorders and exacerbations − note the degree of success of treatment (judged by control/ relief of symptoms)

Conclusions Much of the medical assessment of a patient is derived from the history. Some underlying conditions may be of direct relevance to the safe management of dental patients. It is important that dental practitioners have a sound knowledge of such conditions and are able to put them into context when managing such patients. References:

1. https://pocketdentistry.com/2-history-taking-and-clinical-examination-of-patients-on-a-dental-emergency-clinic/ 2. https://fgdpscotland.org.uk/wp-content/uploads/2016/05/Dent_Update_2015_42_308-315-2.pdf :

References 1. Scully C. Medical Problems in Dentistry 7th edn. Chapter 2: Medical history and risk assessment. Oxford: Elsevier, 2014. 2. Resuscitation Council (UK). Quality Standards for Cardiopulmonary Resuscitation Practice and Training in Primary Dental Care. November 2013. https://www.resus.org.uk/pages/ QSCPR_Main.htm 3. Thomason JM, Girdler NM, KendalTaylor P, Wastell H, Weddell A, Seymour RA. An Investigation into the need for supplementary steroids in organ transplant patients undergoing gingival surgery. J Clin Periodont 1999; 26: 577−582. 4. British National Formulary – online at http://bnf.org 5. Hellstein JW, Marek CL. Bisphosphonate osteochemocrosis (bis-phossy jaw): is this phossy jaw of the 21st century? J Oral Maxillofac Surg 2005: 63 682−689. 6. Khan A. Osteonecrosis of the jaw and bisphosphonates. Br Med J 2010; 340: c246. 7. Migliorati CA, Casigalia J, Epstein J, Jacobsen PL, Siegel MA, Woo SB. Managing the care of patients with bisphosphonate-associated osteonecrosis: an American Academy of Oral Medicine position paper. J Am Dent Assoc 2005; 136: 1658−1668. 8. Meechan JG, Seymour RA. Drug Dictionary for Dentistry. Oxford: Oxford University Press, 2002. 9. Worsley DJ, Jones K, Marshman Z. Patients are asking about e-cigarettes. What do we tell them? Br Dent J 2014; 217: 91−95. 10. Brown S, Greenwood M, Meechan JG. General medicine and surgery for dental practitioners 5: Psychiatric disorders. Br Dent J 2010; 209(1): 11−16. 11. Longmore M, Wilkinson I, Davidson E, Foulkes A, Mafi A. Oxford Handbook of Clinical Medicine 8th edn. Oxford: Oxford University Press, 2010. 12. Dayer MJ, Jones S, Prendergast B, Baddour LM, Lockhart PB, Thornhill MH. Incidence of infective endocarditis in England, 2000-13: a secular trend, interrupted time-series analysis. Lancet 2014; Nov 18: pii: S0140-6736(14)62007-9. Last accessed 29/06/2019

Cannabis: miracle or mystery In 2017, the Constitutional Court of South Africa, the country’s highest court, ruled that the personal use of cannabis is no longer a criminal offence. In a unanimous decision, the court ruled that the ban on private possession and consumption, and cultivation of the plant for own use is unconstitutional.[1]

Despite the fact that trading in cannabis or cannabis based products were still illegal, the use of cannabis oil for insomnia, joint aches, cancer and various other ailments gained popularity. In May 2019 the Minister of Health signed an exemption that states for the next 12 months at least, "preparations" containing CBD will fall entirely outside the scheduling system that controls drugs in South Africa. (CBD or cannabidiol is a chemical compound derived from the Cannabis plant) That makes such CBD preparations legal to sell – by anyone, not just pharmacists – without prescription. The exemption comes with two conditions: the maximum daily dose of CBD must be 20 milligrams or less, and the product cannot claim to cure or treat any specific condition. It may only advertise "general health enhancement", or "health maintenance", or promise "relief of minor symptoms", as long as those symptoms are not linked to a disease or disorder. [2]. Read the full notice as published in the Government Gazette here: https://www.greengazette.co.za/notices/medicines-and-related-substances-act-101-1965-exclusion-of-certain-preparations-containing-cannabidiol-cbd-from-operation-of-certain-provisions-of-the-act_20190523-GGR-42477-00756 As we see in Dr Greenwood’s article, the effect of natural medicines cannot be discounted in our treatments. In May 2017 Dimentions of dental Hygiene published an article by Anna Matthews, RDH, MS and Sandra Stramoski, RDH, MSDH on the therapeutic potential of medical marijuana. Here follow an abstract of the article:

There is evidence of effectiveness of cannabinoid-based drugs and plant-derived cannabis in the

management of cancer, human immunodeficiency virus infection/acquired immune deficiency

syndrome (HIV/AIDS), epilepsy, multiple sclerosis, and chronic pain.2,3 Further therapeutic

potential in many other diseases and conditions explains the broad support for ongoing

investigation and use by the medical community.4 Oral health professionals may expect an

increase in the number of patients reporting medical or recreational cannabis use. Therefore, they

should be prepared to evaluate adverse oral effects; provide counseling, education, and referrals;

and ensure safe treatment outcomes while maintaining an ethical and compassionate professional

approach.

Marijuana is mainly derived from two plant species: Cannabis sativa and Cannabis indica.5The

three most commonly used plant extracts are marijuana, derived from the dried leaves and

flowers; hashish, a resin extract of the flower head; and hash oil, a concentrated fluid from

hashish. These extracts differ in their potency based on the percentage of the active ingredient,

delta-9 tetrahydrocannabinol (THC). As plant-derived cannabis products are illegal under current

federal law, they have not been regulated and evaluated by the US Food and Drug Administration

(FDA), resulting in great variability of potency and purity.6,7 This can result in potential legal

liability for providers, in addition to raising the issues of abuse and addiction, unknown medical

and psychiatric risks, and drug interactions.

Marijuana contains more than 100 cannabinoids, as well as 400 chemicals including aromatic

hydrocarbons, benzopyrene, and nitrosamines, which, when released in cannabis smoke, can be

carcinogenic.8 Cannabinoids are chemical compounds that can bind to cannabinoid receptors

found in many tissues and organs. They include phytocannabinoids, synthetic cannabinoids, and

endocannabinoids. The two main phytocannabinoids are THC and cannabidiol (CBD). In addition

to being responsible for the psychoactive properties of marijuana, THC has analgesic, anti-emetic

(anti-nausea), anti-inflammatory, and antioxidant effects, while CBD has anxiolytic (inhibits

anxiety) , antipsychotic, and anticonvulsive properties.9 These compounds can bind to the

cannabinoid receptors located in tissues and organs, including the central nervous system,

peripheral neurons, immune cells, heart, lungs, and endocrine tissue.9

CANNABINOID-BASED DRUGS

Unlike the endocannabinoids produced in the human body and the plant-derived

phytocannabinoids, synthetic cannabinoids are compounds produced in the laboratory that can

bind to the cannabinoid receptors.10 Two of the cannabinoid-based synthetic THC drugs—

dronabinol and nabilone—have been approved by the FDA since 1985 as Schedule III and

Schedule II drugs, respectively. As such, these drugs are not restricted, other than special

precautions due to their scheduling, and can be prescribed by medical and oral health providers in

the US within their scope of practice.

.

Dronabinol, available in several strengths as a capsule and a liquid preparation, can improve

appetite loss associated with HIV/AIDS, and may also be prescribed for severe nausea and

vomiting associated with chemotherapy. It has also been studied for muscle spasticity and pain

associated with multiple sclerosis and paraplegia.11 Nabilone is FDA-approved for nausea and

vomiting due to cancer chemotherapy, and has been studied for chronic pain, sleep therapy, and

spasticity associated with multiple sclerosis.11,12Both drugs are effective in reducing nausea and

vomiting and for appetite stimulation, but are usually prescribed only if first-line anti-emetics

have not been successful, due to more frequent short-term adverse effects.11

A number of other synthetic cannabinoid-based drugs are under investigation and/or in clinical

trials for previously described conditions and for other indications, such as brain injury and anti-

tumor properties (dexanabinol) and multiple sclerosis-related spasticity, scleroderma fibrosis, and

arthritic pain (ajulemic acid).13

The most common adverse effects associated with orally ingested dronabinol and nabilone are

dizziness, sedation, ―feeling high,‖ and dysphoria (uneasiness). Patients may prefer the

cannabinoid-based drugs to a first-line anti-emetic, such as procholperazine, despite more

frequently reported side effects.12

BOTANICAL CANNABINOIDS

Nabiximols is effective in reducing symptoms of muscle spasticity, pain, and overactive bladder

in patients with multiple sclerosis and for neuropathic pain associated with other

conditions.2 Additionally, improvement of activities of daily living and quality of life measures

were noted in several published trials.14

FIGURE 1. This

sublingual lesion is

an adverse effect of

nabiximols mucosal

spray SCULLY C.

CANNABIS; ADVERSE

EFFECTS FROM AN

OROMUCOSAL

SPRAY. BDJ.

2007;203:E12–E12

Nabiximols—an equal mixture of THC and CBD—is of particular interest to oral health

professionals. It is delivered as an oral mucosal spray to the buccal and sublingual tissues.

Besides common initial adverse effects of dizziness, sleepiness, unsteadiness, taste changes,

burning oral mucosal ulcerations, and reversible lesions appearing as white patches or reddened

irritations can occur at the site of administration (Figure 1).15 Patients are advised to rotate the

area of application to avoid this effect. Notably, long-term use (several months) of nabiximols

spray has not been associated with drug tolerance, abuse, or withdrawal symptoms.14

A proprietary formulation of plant-derived pure CBD is in clinical trials for the treatment of

several severe infant-onset epilepsy disorders. This CBD extract in an elixir form was given fast-

track, as well as orphan drug status by the FDA in 2014, indicating its potential use for rare, but

life threatening conditions that have been previously drug and treatment resistant. These include

Dravet syndrome Lennox-Gastaut syndrome (forms of epilepsy), , tuberous sclerosis complex,

and infantile spasms. Results of controlled studies have shown 39% to 44% reductions in

monthly seizures, and a favorable safety profile.16 CBD does not cause the psychotropic effects of

THC—which is key, considering that the target population is predominantly children.

MEDICAL MARIJUANA

For any treatment, including medical marijuana, the most crucial questions for patients and

providers are: how effective it is for the condition being treated, and what are the short- and long-

term adverse effects? To provide the most comprehensive in-depth review of the available

evidence regarding marijuana use and its health effects, the National Academies of Sciences,

Engineering, and Medicine published a report in 2017 that summarized what is known about the

therapeutic effects of marijuana in the management of various diseases/conditions.2 Also

examined were the relationship between marijuana and cancer, cardio-metabolic risk, respiratory

disease, immunity, injury, and death. The most substantial evidence of therapeutic effects of

cannabis or cannabinoids (including approved oral cannabinoid-based drugs discussed above) is

in treatment of chronic pain in adults, as anti-emetics in treatment of chemotherapy-induced

nausea and vomiting, and in improving multiple sclerosis spasticity symptoms. There is also

moderate evidence of cannabis/cannabinoids effectiveness in improving sleep in individuals with

sleep disturbance associated with several conditions (chronic pain, fibromyalgia, and others). For

many other diseases/conditions under active investigation, including HIV/AIDS, Tourette

syndrome, anxiety, post-traumatic stress disorder (PTSD), epilepsy, Huntington’s disease,

Parkinson’s disease, dementia, depression, traumatic brain injury, and amyotrophic lateral

sclerosis (ALS), there is limited or insufficient evidence because findings are based on small-

scale, short-duration studies—in some cases without proper control groups. The committee

highlighted the need for research of therapeutic effects of cannabis/cannabinoids in these

diseases, especially PTSD and epilepsy, as a significant number of patients are using cannabis for

management of these conditions.2

Other, less studied but potentially important effects of cannabis/cannabinoids include their anti-

tumoral properties demonstrated in the preclinical studies of several cancers. While more

evidence from clinical studies, which are underway for glioma (type of brain tumor), is needed, it

was demonstrated that THC can be safely injected intratumorally.20 With their better tolerability

profiles than currently available chemotherapeutics, if shown effective as anti-neoplastic agents,

cannabinoid-based drugs may open a new frontier in cancer treatment. Additionally, their ability

to modulate the immune system by binding to the CBD receptors located on the immune cells,

prompted rigorous investigations into the effects of cannabinoids in autoimmune

diseases/conditions associated with inflammation. In animal and human studies, cannabinoids

have shown immunosuppressive effect, with potential applications in MS, rheumatoid arthritis,

scleroderma, inflammatory bowel diseases (Crohn’s disease, ulcerative colitis), and neuropathic

pain.21

ADVERSE EFFECTS

Adverse effects of cannabis, including synthetic and plant-based cannabinoids in various forms of

administration (oral, topical, inhalation), were summarized in a 2015 systematic review published

by the Journal of the American Medical Association.11 Notably, this extensive analysis focused

exclusively on medical marijuana. The most common short-term adverse effects were dizziness,

dry mouth, nausea/vomiting, fatigue/drowsiness, disorientation, euphoria, and hallucinations.

Importantly, fatal overdose with cannabis alone has not been reported.6 Possible long-term

effects, including association with cancers of the head and neck, lungs, and esophagus, are

especially concerning with the use of smoked cannabis. Although cannabis use is associated with

cigarette smoking and, like tobacco smoke, cannabis smoke contains carcinogens, there is no

evidence of its association with head and neck and lung cancers, while evidence regarding

esophageal cancer is insufficient.2 Further studies should address the risk factors associated with

cannabis use and specific types of cancers based on their origin and histological and molecular

characteristics.2 Based on the known adverse effects and properties of marijuana, it should be used

with caution in patients with psychiatric, cardiovascular, respiratory, and immunologic diseases.13

Knowledge of the scientific basis for medical cannabis- and cannabinoid-based drugs, as well as

treatment implications and adverse effects of medicinal and recreational use, is essential when

providing health care to the growing number of patients who use them. Comprehensive

assessment of medical history, concurrent medications, vital signs, and investigation of the use

and effects of specific cannabinoid agents is paramount. Evaluation of possible cognitive

impairment that may interfere with valid informed consent is an ethical and legal

responsibility.7 However, the decision to proceed with planned treatment should be based on the

objective assessment and not merely on the patient’s report of cannabis use, whether historical or

recent, medical, or recreational. Physiological and psychoactive action of cannabis depends on

the form, amount/concentration, and route of administration,13 so reviewing this information with

patients is essential. This conversation should be done in a nonjudgmental way to ensure patients’

trust, openness, and compliance. Postponement of treatment, if possible and necessary to ensure

successful outcomes, should be thoroughly explained and documented. Patients should never feel

that they are being punished for their honest disclosure of cannabis use by being re-scheduled or

denied treatment.7

CONCLUSION

A review of the scientific evidence calls for more investigation to evaluate the effectiveness and

health effects of cannabinoid-based drugs and therapies. Currently, rigorous research is subject to

disharmony between federal and state laws, which creates uncertainty for health care

professionals and scientists who must rely on more substantial evidence. Oral health professionals

face the challenge of treating patients who may be currently using some of the existing therapies,

or experiencing conditions for which these drugs may potentially benefit or harm them.

Additionally, providing patients with current scientific information and clarifying possible

misinformation on cannabis is essential in the performance of safe, ethical, and compassionate

treatment.

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2. National Academies of Sciences, Engineering, Medicine. The Health Effects of Cannabis and Cannabinoids: The Current State

of Evidence and Recommendations for Research. Washington, DC:National Academies Press; 2017.

3. Adler JN, Colbert JA. Clinical decisions. Medicinal use of marijuana—polling results. N Engl J Med. 2013;368:e30.

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12. Smith LA, Azariah F, Lavender VT, Stoner NS, Bettiol S. Cannabinoids for nausea and vomiting in adults with cancer receiving

chemotherapy. In: Cochrane Database of Systematic Reviews. Hoboken, New Jersey: John Wiley & Sons Ltd; 2015.

13. Parmar JR, Forrest BD, Freeman RA. Medical marijuana patient counseling points for health care professionals based on trends

in the medical uses, efficacy, and adverse effects of cannabis-based pharmaceutical drugs. Res Soc Adm Pharm. 2016;12:638–

654.

14. Vermersch P, Trojano M. Tetrahydrocannabinol: cannabidiol oromucosal spray for multiple sclerosis-related resistant spasticity

in daily practice. Eur Neurol. 2016;76:216–226.

15. Scully C. Cannabis; adverse effects from an oromucosal spray. BDJ. 2007;203:E12–E12.

16. GW Pharmaceuticals. GW Pharmaceuticals Announces Second Positive Phase 3 Pivotal Trial for Epidiolex (cannabidiol) in the

Treatment of Lennox-Gastaut Syndrome. Available at: gwpharm.com/ about-us/news/gw-pharmaceuticals-announces-second-

positive-phase-3-pivotal-trial-epidiolex. Accessed April 18, 2017.

17. US Food and Drug Administration. Expanded Access (Compassionate Use). Available

at:fda.gov/NewsEvents/PublicHealthFocus/ExpandedAccessCompassionateUse/. Accessed April 18 2017.

18. Devinsky W, Sullivan J, Friedman D, et al. Efficacy and Safety of Epidiolex (Cannabidiol) in Children and Young Adults with

Treatment-Resistant Epilepsy: Update from the Expanded Access Program. 2015.

19. Devinsky O, Marsh E, Friedman D, et al. Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional

trial. Lancet Neurol. 2016;15:270–278.

20. Kramer JL. Medical marijuana for cancer. CA Cancer J Clin. 2015;65:109–122.

21. Katchan V, David P, Shoenfeld Y. Cannabinoids and autoimmune diseases: A systematic review. Autoimmun Rev. 2016;15:513–

528.

22. Shariff JA, Ahluwalia KP, Papapanou PN. Relationship between frequent recreational cannabis (marijuana and hashish) use and

periodontitis in adults in the United States: NHANES 2011-12. J Periodontol. 2017;88:273–280

23. Darling MR, Arendorf TM, Coldrey NA. Effect of cannabis use on oral candidal carriage. J Oral Pathol Med. 1990;19:319–321.

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In March 2018 the same magazine published the following article by Karen M. Portillo, RDH, MSDH, Tammy R. Sanderson, RDH, MSDH and JoAnn R. Gurenlian, RDH, MS, PhD. The abstract from this article focus on both the medicinal and recreational use of marijuana.

Caring for Patients Who Consume Cannabis[4]

With this expansion of legalization, the number of individuals consuming marijuana has

increased and many users may be more comfortable disclosing their cannabis habit. In 2015, 22

million people reported having used some type of cannabis within the past month, and the

number of registered medical marijuana patients is estimated at 2 million.2,3 As such, oral health

professionals need to be knowledgeable about cannabis use, the various forms available, and its

effects on oral and systemic health.

Patients living in states where medical use is legal may consume marijuana to manage pain,

anxiety, depression, migraine headaches, and sleep problems.4 Synthetic oral

tetrahydrocannabinol (THC) medications, such as nabilone and dronabinol, are prescribed to

reduce nausea and vomiting symptoms related to chemotherapy and treatment of acquired

immune deficiency syndrome (AIDS).5,6 Nabiximol oromucosal sprays can help reduce pain and

muscle spasticity in patients with multiple sclerosis, spinal cord injuries, fibromyalgia,

rheumatoid arthritis, and post-traumatic stress disorder.6 Children and adolescents with drug-

resistant epilepsy have experienced a decrease in seizure occurrences with the use of cannabidiol

(CBD).7

TYPES OF MARIJUANA

Weed, hash, and hash oil are the three basic types of cannabis used for recreational and medicinal

purposes.8 Each type contains more than 85 cannabinoids found within the plant, with THC and

CBD being the most well-known.9 THC is the primary psychoactive compound of the plant and it

can create paranoia or anxiety.9 CBD is nonpsychoactive, meaning it does not produce the typical

―high‖ associated with cannabis use.1 Weed consists of the leaves and buds of the

female Cannabis sativa and Cannabis indica plants.9 Hash is made from the resin of the C.

sativa and C. indica plants.2 The resin is dried into blocks, producing an oily, yet solid

substance.9,10 Hash oil is the most potent form of cannabis and requires only a small amount to

produce effects. The average THC potency concentration in weed is 1% to 5%, hash is 5% to

15%, and hash oil is 20% or greater.11

Cannabis can be consumed in four methods: inhalation, orally, topically, and in

suppositories/tampons. Cognitive impairment is caused by the inhalation and oral forms, but not

by the topical or suppository/tampon methods.

INHALATION

The most common method of marijuana use is still through cigarettes, or joints. Marijuana can

also be smoked in a pipe or a bong, which filters the smoke through a liquid, such as water. A

cigar can be hollowed out and the tobacco replaced with marijuana; this is referred to as a blunt.

Marijuana can also be smoked through bubblers, which are mini-bongs, or through hookah

pipes.12,13

The inherent risks associated with smoking have encouraged many users to seek alternative

methods, such as vaping.14 Vaping is when a fine mist generated by heating the marijuana rather

than burning it is inhaled. The cartridge inserted into the vape pen may contain 150 mg, 200 mg,

or 300 mg of THC, with each puff releasing 1.5 mg to 3.0 mg.15 Users who vape often prefer the

quick onset of effects (average of 8 minutes) and the ability to determine the dosage.16

Another type of inhaled marijuana is dabbing. This method uses hash oil that is made into a wax.

Placed in a glass pipe or bong, the wax is then heated to produce a vapor. Dabbing produces an

intense high that can provide a powerful dose of THC. The dabbing method can be dangerous due

to the heating of glass, which can cause explosions and generate chemical inhalants.17

ORAL FORM

Edible and oral types of marijuana can be taken as a capsule or administered sublingually.

Marijuana can also be added to foods or beverages. Unlike smoking, vaping, or dabbing, edibles

must be digested and metabolized before the user can feel the effects. Edibles can present a

dosing challenge and their intensity is much greater, causing full-body, psychoactive effects with

longer duration times.16

The pill forms of marijuana can be prescribed to treat vomiting and nausea.5,6 Dronabinol is a

capsule and contains THC in sesame oil.13 Some negative effects have been reported, including

difficulty keeping the pill down during periods of vomiting, longer time to take effect, and high

cost.16 One advantage of the pill form is reduced exposure to the carcinogens found in marijuana

smoke.

Other oral forms of cannabis include tinctures or oromucosal sprays that are applied sublingually.

A highly concentrated and very potent mixture of liquid cannabis can be dropped (tinctures) or

sprayed under the tongue for a rapid response (5 minutes to 30 minutes). Sprays can cause a

burning sensation and irritate the tissues, however, users report an appreciation of their portability

and discreetness.13,16

TOPICAL AND ALTERNATIVE FORMS

Some cannabis delivery methods, such as topical creams and oils, can provide localized pain

relief and decreased inflammation without the cerebral stimulation. This is an excellent option for

patients who need pain relief but want to remain clear headed.18

Cannabis suppositories that can be inserted vaginally, like a tampon, may help reduce severe

menstrual cramping or those inserted rectally may reduce nausea. These serve as alternatives for

patients who cannot tolerate edibles or are opposed to smoking, vaping, or dabbing.18

Rectal cannabis suppositories have an efficiency rate between 50% to 70%, and produce

predictable effects.18 This differs from inhaled cannabis, which is about 10% to 25% efficient

(depending on amount and frequency smoked, vaped, or dabbed).18 Similarly, the edible forms of

cannabis are approximately 20% efficient with inconsistent effects.18

ADVERSE EFFECTS

While public acceptance of marijuana use continues to grow, it can cause physical, psychological,

cognitive, and psychosocial effects.19 This risk of addiction is significantly greater with

adolescent onset use vs adult onset use.19,20 Systematic reviews and research studies have found

that marijuana use may be related to other complications, such as myocardial infarction (MI);

ischemic stroke and emboli; acute kidney injury; seizures; psychiatric problems, such as

psychosis, mania, paranoia, and self-harm and suicidal behaviors; hyperemesis, respiratory

problems (wheezing, shortness of breath, cardiopulmonary disorder, spontaneous pneumothorax,

and increased lung cancer risk); nervous system disorders; and relapse of multiple sclerosis

symptoms. Additional reported effects include tachycardia; nausea; dizziness; dry mouth; fatigue;

confusion; loss of balance; hallucination; impaired executive functioning, processing speed,

social functioning, and driving ability; low academic achievement; poor job performance; and

increased likelihood of using other illicit drugs.19,21–35 Studies have shown that cannabis smoking

decreases psychomotor skills and alters the activity of the brain involved in cognition.35–37 Zalesky

et al38 demonstrated that cannabis use during adolescence and early adulthood is hazardous to the

white matter of the developing brain, affecting cognition and memory, and increasing the risk of

psychosis, depression, and anxiety disorders.

ORAL CARE CONSIDERATIONS

Cannabis use impacts oral health. Chronic marijuana smokers have poorer oral health including

higher decayed, missing, and filled teeth index scores, more plaque, and poor gingival

health.39,40 Inflammation of the gingiva may appear erythemic(reddening of the skin) with

leukoplakic (white) patches. Rawal et al41 reported two cases of patients with a history of

marijuana use and associated gingival enlargement similar to phenytoin-induced enlargement.

Another side effect of smoking marijuana is xerostomia. Smoking and chewing cannabis can lead

to changes in the oral epithelium, called cannabis stomatitis.40 Leukoedema (blue, grey or white

appearance of mucosae) and hyperkeratosis are other symptoms that oral health professionals

should look for during the intraoral assessment. As inhaled cannabis users are at greater risk for

oral cancer, clinicians need to perform a thorough inspection of the oral soft tissues, paying

attention to the anterior floor of the mouth and tongue.

Although rare, smoking cannabis has been associated with MI. The risk of MI increases fivefold

in the first hour after inhaling cannabis.42 This may be caused by an elevated oxygen demand in

an environment where oxygen has been depleted due to carboxyhemoglobin, which will increase

heart rate, blood pressure, and vasospasm.31,42 As such, local anesthesia with epinephrine should

be administered with caution to patients who have recently used marijuana. A thorough medical

history should be reviewed, including recording of vital signs prior to treatment.43 Precautionary

measures should be taken with patients who present with tachycardia, as serious acute cardiac

effects may occur.43 It is unclear how long cannabis is detectable in the body and how long the

effects of consumption last. Therefore, oral health professionals should be aware that cannabis

may still be present in a patient’s system upon his or her report of recent use.

CONSENT FOR CARE

Cannabis can impair decision making, memory, and behavior, which impacts patients’ abilities to

provide proper consent for treatment. Determining whether patients who have disclosed

marijuana use can consent to care presents a legal challenge for oral health professionals.44

As with any medication use, full disclosure is encouraged. Patients may avoid mentioning their

cannabis use if they feel the oral health professional will be judgmental. Patients may also feel

they are being punished if the clinician refuses to see them once cannabis use has been disclosed.

On the other hand, oral health professionals are obligated to provide dental care in a safe manner,

using professional judgement to determine if the patient has the cognitive ability to consent for

treatment.

First, a comprehensive assessment of care should occur. This should include a review of social,

dental, and medical histories, including the type of cannabis used, recording vital signs, exposing

appropriate radiographs, charting extra/intraoral tissues, and assessing periodontal and caries

risks.45 After the assessment phase, the care plan can be developed in collaboration with the

patient. The clinician should explain the potential negative interactions that could occur between

local anesthesia or nitrous oxide and cannabis.44 For patients who use medical marijuana,

clinicians may want to consult with their physicians so the oral health and medical professionals

can work in tandem to provide coordinated, quality patient care. Patients should be educated

about their increased risk for oral diseases and the available options for treatment of such

problems.

Direct questions concerning cannabis use should be asked (Table 2 provides examples).

Depending on the type of cannabis and whether the drug remains in patients’ systems, oral health

professionals must determine whether they are legally competent to consent for care, as not all

forms of cannabis cause cognitive impairment. Patients’ responses should be documented in their

charts. Regardless of the legal status of marijuana where patients reside, if they are cognitively

impaired, they are not legally authorized to consent to care, and oral health professionals would

be prudent to postpone treatment.44,45 A patient using medical marijuana may have a caregiver who

holds a power of attorney and can consent to care. However, oral health professionals would still

need to consider the risk of drug interactions if the patient has cannabis in his or her system.

THE INTOXICATED PATIENT

Some patients who have recently used marijuana may present intoxicated. Signs of marijuana

intoxication include odor of marijuana, tachycardia, orthostatic hypotension (feeling dizzy when

getting up), and dry mouth. Symptoms may manifest as impaired concentration and attention,

decreased reaction time, euphoria, relaxation, paranoia, anxiety, increased appetite, and

nausea.46 Patients who present with symptoms of intoxication, abnormal vital signs, for whom an

accurate health history cannot be obtained, or who are experiencing respiratory depression

(respiratory rate < 12), hypoxemia, hypotension, tachycardia, symptomatic hypoglycemia,

suicidal ideation, or significant withdrawal symptoms, should be referred immediately to a higher

level of care.46

CONCLUSION

Clinicians need to know the oral implications and risks associated with marijuana use. The

clinical environment should promote open discussion, allowing patients to feel safe to openly

disclose their cannabis use, which, in turn, will help oral health professionals administer care in

the safest manner possible.

REFERENCES

1. Governing the States and Localities. State Marijuana Laws in 2018 Map. Available at: governing.com/gov-data/state-marijuana-

laws-map-medical-recreational.html. Accessed February 8, 2018.

2. Substance Abuse and Mental Health Services Administration. Key Substance Use and Mental Health Indicators in the United

States: Results from the 2015 National Survey on Drug Use and Health. Available at:

samhsa.gov/data/sites/default/files/NSDUH-FFR1-2015/NSDUH-FFR1-2015/NSDUH-FFR1-2015.pdf Accessed February 8,

2018.

3. Marijuana Policy Project. Medical Marijuana Patient Numbers. Available at: mpp.org/issues/medical-marijuana/state-by-state-

medical-marijuana-laws/medical-marijuana-patient-numbers/. Accessed February 8, 2018.

4. Ogborne AC, Smart RG, Weber T, Birchmore-Timney C. Who is using cannabis as a medicine and why: an exploratory study. J

Psychoactive Drugs. 2000;32:435–443.

5. Bostwick JM. Blurred boundaries: the therapeutics and politics of medical marijuana. Mayo Clin Proc. 2012;87:172–186.

6. Howard P, Twycross R, Shuster J, Mihalyo M, Wilcock A. Cannabinoids. J Pain Symptom Manage. 2013;46:142–149.

7. Devinsky O, Marsh E, Friedman D, et al. Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional

trial. Lancet Neurol. 2016;15:270–278.

8. Versteeg PA, Slot DE, van der Velden U, van der Weijden GA. Effect of cannabis usage on the oral environment: a review. Int J

Dent Hyg. 2008;6:315–320.

9. Rella JG. Recreational cannabis use: pleasures and pitfalls. Cleve Clin J Med. 2015;82:765–772.

10. United States Department of Justice Drug Enforcement Adminstration. Drugs of Abuse. Available at: dea.gov/pr/multimedia-

library/publications/drug_of_abuse.pdf. Accessed February 8, 2018.

11. US Department of Transportation. Marijuana-Impaired Driving: A Report to Congress. Available at:

nhtsa.gov/sites/nhtsa.dot.gov/files/documents/812440-marijuana-impaired-driving-report-to-congress.pdf. Accessed February 8,

2018.

12. US Drug Enforcement Administration. Drug Fact Sheet: Marijuana. Available at: dea.gov/pr/multimedia-

library/publications/drug_of_abuse.pdf#page=74. Accessed February 8, 2017.

13. National Institute on Drug Abuse. Marijuana/Cannabis. Available at: dea.gov/druginfo/factsheets. shtml. Accessed February 8,

2018.

14. DP T. Effects of marijuana smoking on the lung. Ann Am Thorac Soc. 2013;10:239-247.

15. National Institute on Drug Abuse. Marijuana: Drug facts. Available at: drugabuse.gov/publications/drugfacts/marijuana.

Accessed February 8, 2018.

16. Huestis MA. Human cannabinoid pharmacokinetics. Chem Biodivers. 2007;4:1770–1804.

17. Stogner JM, Miller BL. Assessing the dangers of ―dabbing:‖ mere marijuana or harmful new trend? Pediatrics. 2015;136:1–3.

18. Hutton H. Beyond THC: exploring the topical uses of cannabis. Journal of the American Herbalists Guild. 2014;12(3):40-44.

19. Feeney KE, Kampman KM. Adverse effects of marijuana use. Linacre Q. 2016;83:174–178.

20. Chen CY, Storr CL, Anthony JC. Early-onset drug use and risk for drug dependence problems. Addict Behav. 2009;34:319–322.

21. Volkow ND, Baler RD, Compton WM, Weiss SR. Adverse health effects of marijuana use. N Engl J Med. 2014;370:2219–2227.

22. Wang T, Collet JP, Shapiro S, Ware MA. Adverse effects of medical cannabinoids: a systematic review. CMAJ. 2008;178:1669–

1678.

23. Gibbs M, Winsper C, Marwaha S, Gilbert E, Broome M, Singh SP. Cannabis use and mania symptoms: a systematic review and

meta-analysis. J Affect Disord. 2015;171:39-47.

24. Faber G, Smid HG, Van Gool AR, Wunderink L, van den Bosch RJ, Wiersma D. Continued cannabis use and outcome in first -

episode psychosis: data from a randomized, open-label, controlled trial. J Clin Psychiatry. 2012;73:632–638.

25. Kuepper R, van Os J, Lieb R, Wittchen HU, Hofler M, Henquet C. Continued cannabis use and risk of incidence and persistence

of psychotic symptoms: 10 year follow-up cohort study. BMJ. 2011;342:d738.

26. Arseneault L, Cannon M, Poulton R, Murray R, Caspi A, Moffitt TE. Cannabis use in adolescence and risk for adult psychosis:

longitudinal prospective study. BMJ. 2002;325:1212–1213.

27. Large M, Sharma S, Compton MT, Slade T, Nielssen O. Cannabis use and earlier onset of psychosis: a systematic meta -

analysis. Arch Gen Psychiatry. 2011;68:555–561.

28. Marconi A, Di Forti M, Lewis CM, Murray RM, Vassos E. Meta-analysis of the association between the level of cannabis use

and risk of psychosis. Schizophr Bull. 2016;42:1262–1269.

29. Jouanjus E, Lapeyre-Mestre M, Micallef J, French Association of the Regional A, Dependence Monitoring Centres Working

Group on Cannabis C. Cannabis use: signal of increasing risk of serious cardiovascular disorders. J Am Heart Assoc.

2014;3:e000638.

30. Mukamal KJ, Maclure M, Muller JE, Mittleman MA. An exploratory prospective study of marijuana use and mortality following

acute myocardial infarction. Am Heart J. 2008;155:465-470.

31. Mittleman MA, Lewis RA, Maclure M, Sherwood JB, Muller JE. Triggering myocardial infarction by marijuana. Circulation.

2001;103:2805–2809.

32. Wolff V, Lauer V, Rouyer O, et al. Cannabis use, ischemic stroke, and multifocal intracranial vasoconstriction: a prospective

study in 48 consecutive young patients. Stroke. 2011;42:1778–1780.

33. Martinasek MP, McGrogan JB, Maysonet A. A Systematic review of the respiratory effects of inhalational marijuana. Respir

Care. 2016;61:1543–1551.

34. Whiting PF, Wolff RF, Deshpande S, et al. Cannabinoids for medical use: a systematic review and meta-

analysis. JAMA. 2015;313:2456–2473.

35. Battistella G, Fornari E, Thomas A, et al. Weed or wheel! FMRI, behavioural, and toxicological investigations of how cannabis

smoking affects skills necessary for driving. PLoS One. 2013;8:e52545.

36. Li MC, Brady JE, DiMaggio CJ, Lusardi AR, Tzong KY, Li G. Marijuana use and motor vehicle crashes. Epidemiol

Rev. 2012;34:65–72.

37. Asbridge M, Hayden JA, Cartwright JL. Acute cannabis consumption and motor vehicle collision risk: systematic review of

observational studies and meta-analysis. BMJ. 2012;344:e536.

38. Zalesky A, Solowij N, Yucel M, et al. Effect of long-term cannabis use on axonal fibre connectivity. Brain. 2012;135:2245–

2255.

39. Cho CM, Hirsch R, Johnstone S. General and oral health implications of cannabis use. Aust Dent J. 2005;50:70–74.

40. Darling MR, Arendorf TM. Review of the effects of cannabis smoking on oral health. Int Dent J. 1992;42:19–22.

41. Rawal SY, Tatakis DN, Tipton DA. Periodontal and oral manifestations of marijuana use. J Tenn Dent Assoc. 2012;92:26–31.

42. Gunawardena MD, Rajapakse S, Herath J, Amarasena N. Myocardial infarction following cannabis induced coronary

vasospasm. BMJ Case Rep. 2014;12:2014.

43. Malamed SF. Handbook of Local Anesthesia. 6th ed. St. Louis: Elsevier; 2013.

44. Grafton SE, Huang PN, Vieira AR. Dental treatment planning considerations for patients using cannabis: A case report. J Am

Dent Assoc. 2016;147:354–361.

45. Henry RK, Goldie MP. Dental Hygiene: Applications to Clinical Practice. Philadelphia: F.A. Davis Co; 2016.

46. Donroe JH, Tetrault JM. Recognizing and caring for the intoxicated patient in an outpatient clinic. Med Clin North

Am. 2017;101:573–586.

References 1. https://www.businessinsider.co.za/south-africa-constitutional-court-decriminalised-cannabis-weed-dagga-consumption-2018-9 last accessed 25/5/19 2. https://www.businessinsider.co.za/cannabidiol-exemption-to-drug-scheduling-for-a-year-and-cbd-schedule-4-officially-2019-5 last accessed 25/5/19 3. https://dimensionsofdentalhygiene.com/article/the-therapeutic-potential-of-medical-marijuana/ last accessed 25/5/19 4. https://dimensionsofdentalhygiene.com/article/caring-for-patients-who-consume-cannabis/ last accessed 25/5/19 Question time:

Please note, where more than one correct answer apply, all correct answers need to be marked to get the point.

1. When taking a history of the presenting problem, which of the following is not part of the

routine?

a. Marital status of the patient.

b. The nature and timing of any symptoms.

c. Details of any systemic signs or symptoms (such as fever).

d. The success or otherwise of previous treatments.

e. Previous practitioners who have been consulted regarding the same or related

condition(s).

2. Which trimester is the safest to treat a pregnant patient?

a. First

b. Second

c. Third

3. For patients on long-term corticosteroid treatment, the following procedures should be

avoided:

a. Restorative work

b. Extractions

c. Surgical procedures

4. Bisphosphonates are prescribed for:

a. the management of osteoporosis

b. Various forms of bone cancer

c. Leukaemia

5. Patients using cocaine might be more prone to:

a. Loss of gingival tissue and alveolar bone

b. Bruising

c. Rampant caries

6. Where possible, dental treatment should be avoided for at least 3 months after a heart

attack.

a. True

b. False

7. It is legal to sell cannabis based products to cure certain cancers.

a. True

b. False

8. Cannabinoids are:

a. Part of the neurological system

b. What make “dagga”users feel “high”

c. chemical compounds that can bind to cannabinoid receptors found in many tissues and

organs in the human body.

9. For medical purposes:

a. synthetic cannabinoids can be produced in the laboratory that can bind to the

cannabinoid receptors

b. synthetic cannabinoids cannot be produced in the laboratory that can bind to the

cannabinoid receptors

c. both partly true

10. The most common short-term side effects of medical marijuana that will affect the dental

patient is:

a. dizziness

b. dry mouth

c. nausea/vomiting

d. heartburn

e. hallucinations

11. Choose the correct statement:

a. Marijuana smokers are more prone to tooth decay

b. Recreational marijuana smokers are at higher risk of developing oral cancer

c. One may see cell changes on the mucosa of marijuana smokers

d. All of the above

12. Choose the correct statement:

a. Local anesthesia with epinephrine/ adrenaline should be administered with caution to

patients who have recently used marijuana.

b. Local anesthesia with epinephrine/adrenaline can be administered safely to patients

who have recently used marijuana.

13. Complete the sentence: The risk of MI increases fivefold in the first ______ after inhaling

cannabis.

a. 30 minutes

b. Hour

c. 4 hours

14. Patients who present with symptoms of intoxication, abnormal vital signs, for whom an

accurate health history cannot be obtained, or who are experiencing respiratory depression

(respiratory rate < 12), hypoxemia, hypotension, tachycardia, symptomatic hypoglycemia,

suicidal ideation, or significant withdrawal symptoms, should be

a. Refused treatment until rehabilitated

b. Referred immediately to a higher level of care.

c. Treated with local anaesthetic without adrenaline.

15. Patients should be:

a. Encouraged to disclose marijuana use to the practitioner

b. Educated about the possible adverse effects it may have in the mouth and on treatment

c. Treated in a non-judgemental manner.

d. All of the above