Digoxin Flashcards
digoxin
Drug class: digitalis glycoside;positive inotropic agent; slows ventricular response in atrial
fibrillation
MOA: at therapeutic levels, vagotonic effects enhances vagal tone, leading to slowing of
conduction through AV node (rate control); increase calcium flux into myocardial muscle cell,
increasing strength of contraction
PK:F~80%, variable; can also be given slowly IV; redistribution slow (~8 h); Cl 80% renal; T1/2
30-40 h with normal renal function; markedly high Vd (6-7 L/kg)
Toxicity, etc: contraindicated in pts with VF, VT, IHSS, AV block, WPW syndrome, sinus node
disease ;most common ADRs include N,V, visual changes (yellow or green circles around
lights), agitation, nightmares, increased automaticity
Interactions: antacids decrease absorption; quinidine reduces renal clearance, increases Cpss
Special issues: CAUTION when giving to patients with changing renal function, or when
starting quinidine; hold drug prior to cardioversion for Afib
Dose, route: for treatment of CHF, or slowing VR in patients in Afib, may be given IV or PO;
loading dose sometimes used, CAREFULLY; maintenance dose 0.125-0.25 mg po qd in most
patients; monitor Cpss
