Sildenafil fluvoxamine

Others Acetaminophen, amiodarone, carbamazepine, delavirdine, efavirenz, nevirapine, quinidine, repaglinide, sildenafil, tadalafil, trazodone, vardenafil Amiodarone, amprenavir, atazanavir, ciprofloxacin, cisapride, clarithromycin, diltiozem, erythromycin, fluconazole, fluvoxamine, grapefruit juice (in high ingestion), indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, norfloxacin, ritonavir, telithromycin, troleandomycin, verapamil, voriconazole Carbamazepine, efavirenz, glucocorticoids, macrolide antibiotics, nevirapine, phenytoin, phenobarbital, rifabutin, rifapentine, rifampin, St. John s wort... 

GFJ has been shown to increase the exposure of carbamazepine (175), cisapride (176-179), fluvoxamine (184), losartan (188), methadone (189), scopolamine (191), and sertraline (192). However, only the interaction of GFJ with carbamazepine and cisapride seems to be clinically relevant. No alteration in exposure was observed for clozapine (180,181), heophylline (195), halo-peridol (196), and omeprazole (190). Reports of increased pharmacokinetic parameters of clozapine, theophylline, and haloperidol suggest that an interaction is unlikely to be clinically relevant. Contradicting results were reported for itraconazole (185-187), digoxin (75,183), and sildenafil (193,194). An increased effect on concomitant use of diclofenac and GFJ was observed in rats (182). Overall, the clinical relevance for this drug class appears to be low. 

Sexual dysfunction is a common adverse effect of SSRIs and various treatments have been proposed, of which sildenafil is the only strategy with consistent support from controlled trials. Sildenafil is metabolized by CYP3A4, which is inhibited by fluvoxamine. The effects of fluvoxamine (100 mg/day for 10 days) on the pharmacokinetics of sildenafil (50 mg orally) has been evaluated in 12 healthy men (mean age 25 years) using a doubleblind, placebo-controlled, crossover design (46). Fluvoxamine increased the AUC of sildenafil by about... 

Hesse C, Siedler H, Burhenne J, Riedel K-D, Haefeli WE. Fluvoxamine affects sildenafil kinetics and dynamics. J Clin Psychopharmacol 2005 25 589-92. 

Retrospective analysis of clinical study data su ested that SSRIs and tricyclic antidepressants did not alter sildenafil pharmacokinetics. However, in one study fluvoxamine was found to modestly increase the levels and vascular effects of sildenafil. 

Sildenafil is principally metabolised by cytochrome P450 isoenzyme CYP3A4, and to a lesser extent by CYP2C9. Fluvoxamine probably raises sildenafil by inhibition of both of these isoenzymes. Grouping all SSRIs and tricyclics together in a retrospective analysis would not be a sensitive enough technique to have picked up this modest effect of fluvoxamine. 

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