Drugs that have a calming effect or that depress the CNS are referred to as sedatives and hypnotics.

Clinical uses: Anxiety relief. Insomnia. Preaneasthesia.

Anxiolytic: drug used to depress the central nervous system (CNS); prevents the signs and symptoms of anxiety.

Sedatives reduce nervousness, excitability, and irritability without causing sleep.

Hypnotics cause sleep and have a much more potent effect on the CNS than do sedatives.

Using these drugs for long time leads to tolerance and dependence so that you can’t get asleep without having them and the effectiveness decrease.

We should look for the causes of insomnia. Drugs for insomnia should be used for short

time as much as possible.

Sedative-hypnotics can be classified chemically into three main groups:

Barbiturates. Benzodiazepines. Miscellaneous drugs.

Benzodiazepines. Buspirone. Beta-blockers. Antideprassants.

Diazepam. Lorazepam. Midozolam.

All anxiolytic drugs decrease anxiety by reducing overactivity in the CNS.

AnxietySleep disorders-----intermediate andshortSkeletal muscle relaxationSeizure disordersAmnesia-------midazolam Adjuvant therapy for depression Alcohol withdrawal==chlordiazepoxide, clorazepate, diazepam, lorazepam, and oxazepam

known drug allergy. Narrow-angle glaucoma. Pregnancy.

Somnolence, Confusion, Coma, and Diminished reflexes

Do not cause hypotension and respiratory depression unless taken with other CNS depressants

Treatment: symptomatic and supportive. Use Flumazenil as an antidote.

It has varied uses: Treatment of anxiety. Anesthesia adjunct. Anticonvulsant therapy. Skeletal muscle relaxation.

Usual Adult Dose for Benzodiazepine Overdose

Initial dose: 0.2 mg IV one time over 30 seconds.Repeated doses: 0.5 mg may be given every minute.Maximum total dose 3 mg.

Patients responding partially at 3 mg may receive additional doses up to 5 mg.

Most patients respond to 1 to 3 mg.

Is an indirect GABA receptor antagonist insimilar way of action on brain receptors.

Rapid onset of action with short duaration. Administration may preceipitate withdrawal

symptoms in dependent patients or may cause seizure in epileptic patients if he on benzodiazepine treatment.

Side effects: dizziness, nausea and vomiting

Alprazolam: It is effective for short and long treatment of

panic disorders when sympathetic discharge is high and aggressive.

Flurazepam: Long acting. Reduce both sleep induction time and number

of awakening and increases duration of sleep. Causes little rebound insomnia.

Temazepam: Intermediate, useful in patients with

frequent awakening situations.

Triazolam: Short, sleep induction in early insomnia.

Clonazepam: Useful in chronic treatment of epilepsy.

1. Absorption and distribution: The benzodiazepines are lipophilic. They are

rapidly and completely absorbed after oral administration, distribute throughout the body and penetrate into the CNS.

2. Duration of action: The half-lives of the benzodiazepines are

important clinically, because the duration of action may determine the therapeutic usefulness.

Most benzodiazepines, including chlordiazepoxide and diazepam, are metabolized by the hepatic microsomal system to compounds that are also active.

For these benzodiazepines, the apparent half-life of the drug represents the combined actions of the parent drug and its metabolites.

Drug effects are terminated not only by excretion but also by redistribution.

The benzodiazepines are excreted in the urine as glucuronides or oxidized metabolites.

All benzodiazepines cross the placenta and may depress the CNS of the newborn if given before birth. The benzodiazepines are not recommended for use during pregnancy. Nursing infants may also be exposed to the drugs in breast milk.

Drowsiness and confusion. Ataxia at high doses. Cognitive impairment. Psychological and physical dependent. Drug abuse. Withdrawal symptoms: confusion, anxiety,

agitation, restlessness and insomnia. Long acting BDZ are producing less severe

withdrawal symptoms than short acting one.

No sedative action.

No risk of dependence.

Nausea and headache. The actions of buspirone appear to be

mediated by serotonin (5-HT1A) receptors, although it also displays some affinity for D2 dopamine receptors and 5-HT2A receptors.

Beta blockers: propranolol.

Antidepressants.

Insomnia can, however, cause feelings of anxiety, inability to concentrate.

Reasons ????????

Sleep architecture: Rapid eye movement (REM) sleep. Non-REM sleep.

Prolonged sedative-hypnotic use lead to REM interference.

On discontinuance of a sedative-hypnotic drug, REM rebound can occur.

Benzodiazepines. Nonbezodiazepines: Zaleplon and

zolpidem. Ramelteon. Barbiturates.

Nonbenzodiazepines function as benzodiazepine but are chemically distinct from them.

Zaleplon and zolpidem.

Although isn’t a BDZ but can act on their receptor.

It has no anticonvulsant or muscle relaxing. No with withdrawal symptoms and exhibit

minimum rebound insomnia with no or little tolerance in prolonged use.

Rapidly absorb from GIT. Rapid onset and short half life. Adverse effects: night mares, agitation,

headache, GI upset and daytime drowsiness.

Ultra short-acting◦ Thiopental

Short-acting◦ Pentobarbital, secobarbital

Intermediate-acting◦ Butabarbital

Long-acting◦ Phenobarbital.

Ultra short-acting◦ Anesthesia for short surgical procedures,

other uses Short-acting

◦ Sedation/sleep induction and control of convulsive conditions

Intermediate-acting◦ Sedation/sleep induction and control of

convulsive conditions Long-acting

◦ Sleep induction, epileptic seizure prophylaxis

Barbiturates have a very narrow therapeutic index Body System

Adverse Effects CNS Drowsiness, lethargy, vertigo,

mental depression. Respiratory Respiratory depression, apnea,

bronchospasms, cough. GI Nausea, vomiting, diarrhea,

constipation Other Agranulocytosis, hypotension,

Stevens-Johnson syndrome

They act by reducing the nerve impulses traveling to the area of the brain called the cerebral cortex.

Old generation antihistamines have a hypnotic effect as an adverse effect.

Give hypnotics 30 to 60 minutes before bedtime.

benzodiazepines cause REM rebound.

Instruct patients to avoid CNS depressants

Rebound insomnia may occur for a few nights after a 3- to 4-week regimen has been discontinued

Safety is important◦ Keep side rails up, or use bed alarms◦ Do not permit smoking◦ Assist patient with ambulation (especially the

elderly)◦ Keep call light within reach

Monitor for adverse effects