INTRODUCTION TO PHARMACOLOGY

Branches of Pharmacology

• Pharmaceutics – science of preparing & dispensing drugs
• Pharmacodynamics – what the drug does to the body
• Pharmacology – science of drugs
• Pharmacognosy – study of drugs obtained from natural sources
• Pharmacotherapeutics – treatment of pathologic conditions with drugs
• Pharmacokinetics – what the body does to the drug
• Absorption – movement of drug from site of administration to distribution to tissues
• Enteral
• Parenteral
• Topical
• Distribution – transport of drug via bloodstream to its site of action
• Metabolism – chemical alteration of drug to make it inactive
• Liver –organ of drug metabolism
• Cytochrome P450 – enzyme of metabolism from the liver
• Excretion – elimination of drug from body
• Biliary – bound to bile and excreted with feces
• Renal – filtered & excreted by kidneys

Roles of Nurses

• Administering drugs
• Assessing drug effects
• Intervening to make drug regimen more tolerable
• Provide patient teaching

Important Terms

• Agonist - drug that binds to a receptor site to produce an effect
• Antagonist - drug that blocks a receptor site to prevent an effect from occurring
• Half-Life – time for half of the drug to be removed from the body
• Inactive ingredient - gives form (tablet, powder, granule, etc.) to drug
• Sample: cetirizine hydrochloride; hydrochloride is an inactive ingredient