Pharmacology Mnemonics - Flash Cards

Name: Dopamine

Class: Catecholamine

Mech.: ¯ dose ® D1 stim. ­ dose ® b1 stim. Also releases NE from symp. neur. Causes vasodilation in renal, mesenteric, and coronary beds ® ­ renal blood flow, glomerular filtration, and Na⁺ excretion. Also causes ¯ Na⁺ and H₂0 resorption. High doses ® ­ HR. Usu. increases systolic BP and pulse pressure. Low-mod. doses ® static or decreased vasc. resistance. High conc. ® a1 activation ® vasoconstriction ® ­ BP.

Absorption: No oral. IV. Onset w/in 5 min.

Dist.:

Metab.: Catab. by COMT and MAO, esp. in liver and kidneys. Glucuronidation and sulfconjugation

Excretion, t½: Duration of action 10 min. t½: 2 min.

Toxicity/S.E.s: Nausea, vomiting, tachycardia, anginal pain, arrhythmia, headache, hypertension, vasoconstriction. Usu. due to excessive symp activity. Treat by stopping admin. or w/a blockers. Local ischemic necrosis. Contraind. w/pheochromocytomas, uncorrected tachyarrhythm. or vent. fibrillation, MAO inhibitors, furazolidone. Adjust dose w/tricyclics.

Utility: Some shock (e.g., oliguria and low-normal periph. resist, cardiogenic/septic shock).

Name: Norepinephrine

Class: Catecholamine

Mech.: Stim. a and b1, but not b2. Approx equal affinity as EPI at b1, less at a. Causes ­ in systolic & diastolic pressure. CO unchanged or ¯ due to reflexive bradycardia. ­ TPR. Marked vasoconstriction but ­ coronary flow due to ­ myocardial contractility.

Absorption: No oral. Usu slow IV. Poor subcut.

Dist.:

Metab.: Catab. by COMT and MAO, esp. in liver and kidneys. Glucuronidation and sulfconjugation.

Excretion, t½: Short duration (1-2 min)

Toxicity/S.E.s: Less severe than EPI. Anxiety, resp. difficulty, slow forceful heart beat, transient headache. Risk of cardiac arrhythmia ® contraind. w/halogenated hydrocarbon anesthetics. ¯ blood to vital organs. Necrosis at infusion site if extravasated. Contraind. for pregnant women, halog. hydroc. anesthetics, tricyclics.

Utility: Limited value. 1° for shock, certain acute hypotensive states (e.g., hypotension persisting after correction of blood volume deficit). Adjunct in treatment of cardiac arrest w/profound hypertension.

Name: Epinephrine

Class: Catecholamine

Mech.: Stim. a and b receptors. EPI @ NE at a, but EPI>>NE at b2. At normal doses, b actions predominate. At high doses, a actions predominate. IV bolus ® rapid rise in BP (mainly systolic),­ strength of ventricular contraction, ­ HR, arteriolar constrict. in skin, mucosa, splanchnic areas. Slower app. or lower dose ® ¯ diastolic pressure due to ¯ periph resistance; increased pulse pressure. Causes ­ CO due to ­ rate and strength of contraction. Dilates bronchi and iris. Increases blood sugar and liver glycogenolysis.

Absorption: Subcutaneous, inhalation, IV, ophthalmic. Oral ineffective.

Metab.: Catab. by COMT and MAO, esp. in liver and kidneys. Glucuron. & sulfconj.

Excretion, t½: Short duration of action.

Toxicity/S.E.s: Cerebral hemorrhage, cardiac arrhythmias. May induce angina pain in angina patients. Also fear, anxiety, tenseness, restlessness, headache, tremor, weakness, dizziness, pallor, resp. difficulty, heart palpitations. Use w/ caution w/old folk, CV disease, hypertension, diabetes, hyperthyroidism, psychoneuroses, bronchial asthma, emphysema w/degenerative heart disease, and tricyclic drugs.

Utility: Reduce resp. distress due to bronchospasm. DOC for anaphylaxis. Prolong actions of local anesthetics. Restore cardiac fxn after cardiac arrest. Treat local hemostasis, open-angle glaucoma. Also inhibits uterine contractions, reduces mucosal congestion of hay fever, rhinitis, and acute sinusitis. ONLY OTC sympathomimetic for asthma.