Itraconazole Fentanyl

Omeprazole, like cimetidine, can impair benzodiazepine metabolism and lead to adverse effects (SEDA-18, 43). Other drugs, including antibiotics (erythromycin, chloramphenicol, isoniazid), antifungal drugs (ketoconazole, itraconazole, and analogues), some SSRIs (fluoxetine, paroxetine), other antidepressants (nefazodone), protease inhibitors (saquinavir), opioids (fentanyl), calcium channel blockers (diltiazem, verapamil), and disulfiram also compete for hepatic oxidative pathways that metabolize most benzodiazepines, as well as zolpidem, zopiclone, and buspirone (SEDA-22,39) (SEDA-22,41). 

An interaction of itraconazole with fentanyl has been reported in a 67-year-old man with cancer on a stable dose of transdermal fentanyl 50 micrograms/hour (88). He took itraconazole 200 mg bd for oropharyngeal candidiasis, and 24 hours later developed signs of opioid toxicity, which was reversed by withdrawal of fentanyl and replacement with short-acting opioids. 

Mercadante S, Villari P, Ferrera P. Itraconazole-fentanyl interaction in a cancer patient. J Pain Symptom Manage 2002 24(3) 284-6. 

Clinically important, potentially hazardous interactions with acenocoumarol, alfuzosin, aminophylline, anisindione, anticoagulants, buprenorphine, butorphanol, caffeine, carmustine, dobazam, cocoa, dicumarol, dofetilide, duloxetine, epirubicin, eszopiclone, fentanyl, floxuridine, fluorouracil, galantamine, gliclazide, hydromorphone, itraconazole, ketoconazole, lidocaine, meptazinol, midazolam, mizolastine, modobemide, morphine, narcotic analgesics, oxprenolol, oxycodone, pentazocine, phenytoin, posaconazole, prednisone, propranolol, sufentanil, tolazoline, warfarin, xanthines, zaleplon, zofenopril, zolmitriptan, zolpidem... 

Some patients may experience prolonged and increased alfentanil effects if they are given fluconazole or voriconazole. In vitro data surest itraconazole and ketoconazole may interact similarly. Intravenous fentanyl does not appear to interact with itraconazole in healthy subjects, but one case of possible opioid toxicity from transdermal fentanyl has been reported. 

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