Introduction To

Respiratory Care

Pharmacology

CHAPTER 1

Introduction

• Respiratory Care Pharmacology represents the application of pharmacology to the treatment of pulmonary disorders, and more broadly, critical care.

Pharmacology and the Study of Drugs

• Human organism – regulated by chemical agents such as hormones, kinins, and cathecholamines

• “DRUG” – is any chemical that alters the organism’s functions or processes, e.g. oxygen, alcohol, LSD, heparin, epinephrine, or vitamins.

• PHARMACOLOGY – the study of drugs, including their origin, properties and interactions with living organism.

Pharmacology can be subdivided to more specialized topics:

• PHARMACY – the preparation and dispensing of drugs• PHARMACOGNOSY – the identification of sources of

drugs, from plants and animals• PHARMACOGENETICS – the study of the

interrelationship of genetic differences and drug effects• THERAPEUTICS – the art of treating disease with drugs• TOXICOLOGY – the study of toxic substances and their

pharmacologic actions, including antidotes and poison control

NAMING DRUGS• CHEMICAL NAME – the name indicating the

drug’s chemical structure.• CODE NAME – name assigned by a

manufacturer to an experimental chemical that shows potential as a drug

• GENERIC NAME – name assigned to a chemical by the United States Adopted Name (USAN) Council when chemical appears to have therapeutic use and the manufactures wishes to market the drug

• OFFICIAL NAME – in the event that an experimental drug becomes fully approved for general use and is admitted to the USP-NF, the generic name becomes the official name

• TRADE NAME – this is the brand name given by a particular manufacturer and is also known as the propriety name

NAMING DRUGS

– Code Name : ICI 204,219– Chemical Name: 4-(5-cyclopentyloxy

carbonylamino-1-methyl- indol-3-ylmethyl)- 3-methoxy- N-o-tolysulfonylbenzamide

– Official Name: zafirlukast– Generic Name: zafirlukast– Trade Name: Accolate (Zeneca

Pharmaceuticals)

BRIEF HISTORY: Legislation Affecting Drug

• 1906 – first Food and Drugs Act passed by Congress; the United States Pharmacopeia (USP) and the National Formulary (NF) are given official status

• 1919 – the Harrison Narcotic Act is passed to control the importation, sale, and distribution of opium and its derivatives, as well as other narcotic analgesics

• 1938 – the Food, Drug, and Cosmetic Act becomes law. – protect the public health and protect physicians from irresponsible drug manufacturers. Act is enforced by the FDA (Food and Drug Administration)

BRIEF HISTORY: Legislation Affecting Drug (cont.)

• 1952 – the Durham-Humphrey Amendment defines the drugs that may be sold by the pharmacist only by prescription

• 1962 – the Kefauver-Harris Law is passed as an amendment to the Food , Drug, and Cosmetic Act of 1938. Act requires proof of safety and efficacy of all drugs introduced since 1938. Drugs in use prior to that have not been reviewed but are under study.

BRIEF HISTORY: Legislation Affecting Drug (cont.)

• 1971 – the Controlled Substance Act becomes effective; this act lists requirements for the control, sale, and dispensation of narcotics and dangerous drugs.

• Schedule 1-5 defines drugs of decreasing potential for abuse, increasing medical use, and decreasing physical dependence

• Sched 1 – Heroin, Marijuana, LSD, peyote and mescaline• Sched 2 – Opium, morphine, codeine, cocaine,

amphetamines• Sched 3 – Glutethimide, paregoric, and barbituates• Sched 4 – Phenobarbital, barbital, chloral hydrate,

meprobamate, and paraldehyde• Sched 5 – Narcotics containing nonnarcotics in mixture

form, such as cough preparation

SOURCES OF DRUG INFORMATION

• United States Pharmacopeia and National Formulary – giving drug standards in the United States

• United States Pharmacopeia(USP) – established in 1820 as a private medical effort; given official status in 1960

• National Formulary(NF) – published in 1888• Physician’s Desk Reference (PDR) – is prepared by

manufacturers of drugs. This annual volume provides useful information.

• Hospital Formulary – is published by the American Society of Hospital Pharmacist

SOURCES OF DRUGS• Naturally occurring drugs - Egyptian papyrus

records, ancient Chinese and Central American civilization

• Animal: thyroid hormone, insulin • Plants: khellin (Ammi visnaga), atropine

(belladonna alkaloid), digitalis (foxglobe), reserpine (rauwolfia serpentines), eucalyptus, pine, anise

• Minerals: copper sulfate, magnesium sulfate (epsom salts), mineral oil (liquid hydrocarbons

• Synthetic derivatives

Major Steps in the Process of Marketing a Drug in the United States

• Isolation and identification of the chemical• Animal studies– General effects and special effects– Toxicology study

• Investigational New Drug (IND) Approval– Phase 1 – small number, healthy subjects– Phase 2 – small number, subjects with disease– Phase 3 – large multicenter studies

• New Drug Application (NDA)– Reporting system for first 6 months

The Thalidomide Story• 1950 – released outside the United States• Prescribed to pregnant women to prevent or

lessen morning sickness and to aid in sleeping• Drug causes severe birth deformities• Currently, thalidomide is used worldwide for the

treatment of leprosy, reverse weight loss seen in tuberculosis and AIDS, slow viral HIV

• Investigators at Rockefeller University found that it reduces production of cytokine tumor necrosis factor alpha (TNFα) by immune cells that causes tissue wasting, fevers and night sweats

Orphan Drugs

• Is a drug or biological product of the diagnosis or treatment of a rare disease

• Rare is defined as a disease that affects fewer than 200,000 persons

• A drug may be designated as orphan if used for a disease that affects more than 200,000 persons but there is no reasonable expectation of recovering the cost of drug development

The Prescription

• Written order for a drug, along with any specific instructions for compounding, dispensing and taking the drug

• Written by physician, osteopath, dentist, veterinarians and others but not chiropractors and opticians.

Patient Name, Address, DateRx symbol – “recipe” or “take thou”SUPERSCRIPTIONINSCRIPTION

Name and Quantitry of DrugSUBSCRIPTION

Direction to the pharmacistTRANSCRIPTION

“Sig”-write. Intstruction to pxPhysician Signature

Over-the-Counter (OTC) Drugs

• Drugs available to the general population without a prescription

• The strength and the dose may be lower than with a prescription formulation, OTC drugs can be hazardous in normal amounts if their effects are not understood and they can be taken in large quantities, thereby increasing the risk

Generic Substitution

• A physician can indicate to the pharmacist that generic substitution is permitted in the filling of the prescription

• Any manufacturer’s version of the prescribed drug

• Intended to save money

RESPIRATORY CARE PHARMACOLOGY- AN OVERVIEW

Aerosolized Agents Given by Inhalation• Aerosol dose are smaller than those used for the

same purpose and are given systematically• Side effects are usually fewer and less severe with

aerosol delivery than with oral or parenteral delivery

• Onset of action is rapid• Drug delivery is targeted to the respiratory

system• Inhalation is painless, relatively safe, and may be

convenient depending on the specific delivery device used

Related Drug Groups in Respiratory Care• ANTIINFECTIVES – antibiotics, antituberculosis, antivirals• NEUROMUSCULAR BLOCKING AGENTS – curariform

agents• CENTRAL NERVOUS SYSTEM AGENTS – analgesics,

sedatives/hypnotic• ANTIARRHYTHMIC AGENTS – cardiac glycosides,

lidocaine• ANTIHYPERTENSIVE AND ANTIANGINAL AGENTS – beta

blocking agents• ANTICOAGULANTS AND THROMBOTIC AGENTS – heparin• DIURETICS – thiazides or furosemides

Aerosolized Agents GROUPS• Adrenergic agents –Beta-adrenergic: relaxation of smooth muscle

and bronchodilation, reduce Raw and improve ventilatory flow rates in airway obstruction such as COPD, asthma, CF, acute bronchitis–Alpha adrenergic: Epinephrine- topical

vasoconstriction and decongestion• Epinephrine, Isoproterenol, Isoetharine,

Terbutaline, Metaproterenol, Albuterol, Pirbuterol, Bitolterol, Salmeterol…

• Anticholinergic agents–Relaxation of cholinergic-induced

bronchoconstriction to improve ventilatory flow rates in COPD and asthma• Ipratropium bromide

Aerosolized Agents GROUPS

• Mucoactive agents–Modification of the properties of respiratory

tract mucus; current agents lower viscosity and promote clearance secretions• Acetylcysteine• Dornase alfa

Aerosolized Agents GROUPS

• Corticosteroids–Reduce and control the inflammatory

response in the airway usually associated with asthma (lower respiratory tract) or with seasonal or chronic rhinitis (upper respiratory tract)• Dexamethasone, Beclometasone dipropionate,

Triamcinolone acetonide, Flunisolide, Fluticasone propionate, Budesonide

Aerosolized Agents GROUPS

• Antiasthmatic agents– To prevent the onset and development of

the asthmatic response, through inhibition of chemical mediators of inflammation• Cromolyn sodium, Nedocromil sodium,

Zafirlukast, Zileuton

Aerosolized Agents GROUPS

• Antiinfective agents– To inhibit or eradicate specific infective

agents such as Pneumocystis carinii or respiratory syncytial virus• Pentamidine, Ribavirin

Aerosolized Agents GROUPS

• Exogenous surfactants–Approved clinical dose is by direct

intratracheal instillation, for the purpose of restoring a more normal lung compliance in respiratory distress syndrome of the newborn• Colfosceril palmitate, Beractant

Aerosolized Agents GROUPS

Assignment

1. Make a list of abbreviations and symbols with their meanings used in prescriptions (hand written or printed copy) and attach it to your Tickler notebook.

2. In a short bond paper, discuss the generics act of 1988 / republic act no. 6675 and its importance in the field of medical practice.