Cardiac glycosides digoxin

Digoxin is indicated in patients with heart failure and atrial fibrillation. It is also most helpful in patients with a dilated heart and third heart sound. It is usually given only when diuretics and ACE inhibitors have failed to control symptoms. Only about 50% of patients with normal sinus rhythm (usually those with documented systolic dysfunction) will have relief of heart failure from digitalis. Better results are obtained in patients with atrial fibrillation. If the decision is made to use a cardiac glycoside, digoxin is the one chosen in most cases (and the only one available in the USA). When symptoms are mild, slow loading (digitalization) with 0.125-0.25 mg per day is safer and just as effective as the rapid method (0.5-0.75 mg every 8 hours for three doses, followed by 0.125-0.25 mg per day). 

MORACIZINE CARDIAC GLYCOSIDES -DIGOXIN Case reports of heart block when moracizine is co-administered with digoxin Uncertain at present Monitor PR and ECG closely... 

PROPAFENONE CARDIAC GLYCOSIDES Digoxin concentrations may be t by propafenone Uncertain at present Watch for digoxin toxicity check digoxin levels if indicated and 1 digoxin dose as necessary (15-75% suggested by studies)... 

TRAZODONE CARDIAC GLYCOSIDES-DIGOXIN Two reported cases of t plasma concentrations of digoxin after starting trazodone Uncertain at present Watch for digoxin toxicity check levels and 1 dose of digoxin as necessary... 

ST JOHN S WORT CARDIAC GLYCOSIDES -DIGOXIN Plasma concentrations of digoxin seem to be 1 by St John s wort St John s wort seems to i P-gp-mediated intestinal absorption of digoxin Watch for l response to digoxin... 

PROPANTHELINE CARDIAC GLYCOSIDES-DIGOXIN t digoxin levels (30-40%) but only with slow-release formulations Slowed gut transit time allows more digoxin to be absorbed Use alternative formulation of digoxin... 

ALPRAZOLAM, DIAZEPAM CARDIAC GLYCOSIDES-DIGOXIN Alprazolam and possibly diazepam may T digoxin levels, particularly in the over-65s Uncertain at present possibly i renal excretion of digoxin Monitor digoxin levels watch for digoxin toxicity... 

PARASYMPATHOMIMETICS CARDIAC GLYCOSIDES-DIGOXIN Cases of AV block and bradycardia have been reported when edrophonium was co-administered with digoxin Uncertain at present Avoid edrophonium in patients with atrial arrhythmias who are also taking digoxin... 

AMINOSALICYLATES CARDIAC GLYCOSIDES-DIGOXIN Sulfasalazine may 1 digoxin levels. The manufacturers of balsalazide also warn against the possibility of this interaction despite of a lack of case reports Uncertain at present Watch for poor response to digoxin check levels if signs of 1 effect... 

CICLOSPORIN CARDIAC GLYCOSIDES -DIGOXIN t plasma digoxin levels, with risk of toxicity. Digoxin may t ciclosporin bioavailability (15-20%) Attributed to inhibition of intestinal and renal P-gp, which t bioavailability and renal elimination. Digoxin t bioavailability of ciclosporin due to substrate competition for P-gp Watch for digoxin toxicity. Monitor plasma digoxin and ciclosporin levels... 

TACROLIMUS CARDIAC GLYCOSIDES -DIGOXIN Digoxin toxicity (pharmacodynamic) Possibly due to tacrolimus-induced hyperkalaemia and hypomagnesaemia Watch for digoxin toxicity. Monitor potassium and magnesium levels... 

TIZANIDINE CARDIAC GLYCOSIDES -DIGOXIN Risk of bradycardia when tizanidine is given with digoxin Tizanidine has a negative inotropic effect Monitor PR closely... 

MACROLIDES CARDIAC GLYCOSIDES -DIGOXIN Digoxin concentrations may be t by the macrolides Uncertain postulated that macrolides inhibit P-gp in both the intestine (t bioavailability) and kidney (J- clearance). It is possible that alterations in intestinal flora may also have a role Monitor digoxin levels watch for digoxin toxicity... 

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