Drug Quiz #1: Mechanism of Action

Question 1

etomidate (Amidate)

Answer 1

Ultra-short-acting nonbarbiturate general anesthetic (benzylimidazole) used for rapid induction of anesthesia with minimal cardiovascular effects; produces EEG burst suppression at high doses. Decreases endogenous cortisol synthesis via inhibition of 11-beta-hydroxylase

Question 2

protamine (Prosulf)

Answer 2

A highly alkaline protein molecule with a large positive charge, has weak anticoagulant activity when administered alone. When protamine is given in the presence of heparin (strongly acidic and negatively charged), a stable salt is formed and the anticoagulant activity of both drugs is nullified. In the presence of LMWH, protamine incompletely reverses the anti-factor Xa activity of LMWH

Question 3

propofol (Diprivan, TEVA-Propofol)

Answer 3

A short-acting, lipophilic intravenous general anesthetic unrelated to any of the currently used barbiturate, opioid, benzodiazepine, arylcyclohexylamine, or imidazole intravenous anesthetic agents. It causes global CNS depression, presumably through agonism of GABA-A receptors and perhaps reduced glutamatergic activity through NMDA receptor blockade.

Question 4

scopolamine (Transderm Scop)

Answer 4

Blocks the action of acetylcholine at parasympathetic sites in smooth muscle, secretory glands and the CNS; increases cardiac output, dries secretions, antagonizes histamine and serotonin; at usual recommended doses, causes blockade of muscarinic receptors at the cardiac SA-node and is parasympatholytic (ie, blocks vagal activity increasing heart rate)

Question 5

droperidol (Inapsine)

Answer 5

A butyrophenone antipsychotic; antiemetic effect is a result of blockade of dopamine stimulation of the chemoreceptor trigger zone. Other effects include alpha-adrenergic blockade, peripheral vascular dilation, and reduction of the pressor effect of epinephrine resulting in hypotension and decreased peripheral vascular resistance; may also reduce pulmonary artery pressure

Question 6

naloxone (Narcan, Evzio, Kloxxado, Zimhi, RiVive)

Answer 6

Pure opioid antagonist that competes and displaces opioids at opioid receptor sites

Question 7

ketorolac (Toradol)

Answer 7

Reversibly inhibits cyclooxygenase-1 and 2 (COX-1 and 2) enzymes, which results in decreased formation of prostaglandin precursors; has antipyretic, analgesic, and anti-inflammatory properties. Other proposed mechanisms not fully elucidated (and possibly contributing to the anti-inflammatory effect to varying degrees), include inhibiting chemotaxis, altering lymphocyte activity, inhibiting neutrophil aggregation/activation, and decreasing proinflammatory cytokine levels

Question 8

vecuronium (Norcuron)

Answer 8

Blocks acetylcholine from binding to receptors on motor endplate inhibiting depolarization

Question 9

succinylcholine (Anectine, Quelicin)

Answer 9

Acts similar to acetylcholine, produces depolarization of the motor endplate at the myoneural junction which causes sustained flaccid skeletal muscle paralysis produced by state of accommodation that develops in adjacent excitable muscle membranes

Question 10

glycopyrrolate (Robinul)

Answer 10

Blocks the action of acetylcholine at parasympathetic sites in smooth muscle, secretory glands, and the CNS; indirectly reduces the rate of salivation by preventing the stimulation of acetylcholine receptors

Question 11

aminocaproic acid (Amicar)

Answer 11

Binds competitively to plasminogen; blocking the binding of plasminogen to fibrin and the subsequent conversion to plasmin, resulting in inhibition of fibrin degradation (fibrinolysis).