Nefazodone Digoxin

Nefazodone + digoxin —> increased plasma digoxin concentration due to impaired metabolism. 

Drugs that affect nefazodone include general anesthetics, sibutramine, sumatriptan, buspirone, carbamazepine, and propranolol. Drugs that may be affected by nefazodone include alcohol, benzodiazepines, buspirone, carbamazepine, cisapride, digoxin, haloperidol, HMG-CoA reductase inhibitors, MAOIs, propranolol, St. John s wort, cyclosporine, and tacrolimus. 

With the important exception of additive effects when combined with other CNS depressants, including alcohol, BZDs interact with very few drugs. Disulfiram (see the section The Alcoholic Patient in Chapter 14) and cimetidine may increase BZD blood levels, and diazepam may increase blood levels of digoxin and phenytoin. Antacids may reduce the clinical effects of clorazepate by hindering its biotransformation to desmethyidiazepam. Coadministration of a BZD and another drug known to induce seizures may possibly increase seizure risk, especially if the BZD is abruptly withdrawn. Furthermore, as noted earlier, important interactions have been reported among nefazodone, erythromycin, troleandomycin, and other macrolide antibiotics, as well as itraconazole. In each case, metabolism is inhibited, and triazolam levels can increase significantly. 

St. John s wort Mild to moderate depression Gastrointestinal upset, photo-sensitivity. Mild serotonin syndrome with the following medications paroxetine, trazodone, sertraline, and nefazodone. May decrease digoxin levels. May decrease cyclosporine serum concentrations. Combined oral contraceptives—breakthrough bleeding. 

Clinically important, potentially hazardous interactions with barbiturates, carbamazepine, clarithromycin, cyclosporine, CYP3A inhibitors, digoxin, grapefruit juice, itraconazole, ketoconazole, lovastatin, nefazodone, nelfinavir, p-gp inhibitors, phenytoin, rifabutin, rifampin, rifapentin, ritonavir, saquinavir, St John s wort, telithromycin... 

Dockens RC, Greene DS, Barbhaiya RH Assessment of phaimacokinetic and phaimacody-namic drug interactions between nefazodone and digoxin in healthy male volunteers J Clin Pharmacol 996) 36,160-7. 

Nefazodone causes a moderate increase in serum digoxin levels but this is of uncertain clinical importance. Digoxin does not appear to affect the pharmacokinetics of nefazodone. 

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