Pharmacology - Alberta College of Paramedics

Drug Classifications and FamiliesAll drugs are classified in a variety of ways. The most common classifications arethe pharmacologic family, which is the drugs chemical structure and thetherapeutic family, which is the mechanism of action and the resulting therapeuticeffect is has on the body. (refer to the pink section of the CPS).Please note: A particular drug may produce multiple therapeutic effects and as aresult be listed under multiple therapeutic families.There is usually one drug within a family that will be considered the prototype andall other drugs within this family will be compared to it. For example, morphine(opium derivative) is the prototype; all other drugs in the opiate family will becompared to morphine.Knowledge of the following drug families’ major effects and side effects ofmedications is important to prehospital drug therapy, particularly when managingpatients who have taken these drugs.Table P-11 Drug Families Common in the Prehospital Care Settingo Receptors and ActionsDrug Family Major effects Side-EffectsOpiatesMorphine, Heroine, Codeine,Demerol (Meperidine),Dilaudid (Hydromorphone),Talwin,Oxycodone (Percodan),MethadoneHallucinogensLysergic acid diethylamide(LSD), Mescaline, nutmeg,mace, MDMA (Ecstasy) andMDEA (Eve)These drugs act by binding toand stimulating CNSreceptors responsible for therelease of endorphins andenkephalins. Thesesubstances produce themarked effects of narcoticsby producing euphoria, asense of well-being andincreased pain tolerance.All these impart their effectsby direct chemical influenceof CNS tissue.Side effects are directlyrelated to the CNS depressantproperties of this family ofmedication. Decrease levelof responsiveness, decreasedrespiration rate and depth aswell as constriction of pupilsare often seen.Cardiovascular effects mayresult in presentation ofhypotension.Dependent on agent,intoxication effects mayrange from visualdisturbances to directrespiratory and cardiacdepression.EMT Pharmacology 41