Ritonavir with voriconazole

The current use of protease inhibitors and voriconazole is predicted to interfere with the metabolism of both drugs. Studies suggest that ritonavir decreases voriconazole levels, but no interaction was seen between indinavir and voriconazole in one study. 

IMATINIB 1. ANTIBIOTICS - clarithromycin, erythromycin 2. ANTIFUNGALS -fluconazole, itraconazole, ketoconazole voriconazole 3. ANTIVIRALS -efavirenz, ritonavir 4. GRAPEFRUIT JUICE 5. H2 RECEPTOR BLOCKERS - cimetidine t imatinib levels with t risk of toxicity (e.g. abdominal pain, constipation, dyspnoea) and of neurotoxicity (e.g. taste disturbances, dizziness, headache, paraesthesia, peripheral neuropathy) Due to inhibition of CYP3A4-mediated metabolism of imatinib Monitor for clinical efficacy and for the signs of toxicity listed, along with convulsions, confusion and signs of oedema (including pulmonary oedema). Monitor electrolytes and liver function, and for cardiotoxicity... 

Clinically important, potentially hazardous interactions with amiodarone, azithromycin, bepredil, bosentan, bretylium, cisapride, clarithromycin, disopyramide, erythromycin, erythromycin fluconazole, fluoxetine, fluvoxamine, grapefruit juice, indinavir, itraconazole, ketoconazole, metronidazole, miconazole, nefazodone, nilotinib, paroxetine, pimozide, probucol, procainamide, quinidine, quinine, ritonavir, saquinavir, sertraline, sotalol, SSRIs, terfenadine, troleandomycin, voriconazole, zileuton, ziprasidone... 

Clinically important, potentially hazardous interactions with acetylcysteine, adenosine, aprepitant, aripiprazole, buprenorphine, caffeine, charcoal, clarithromycin, clobazam, dorazepate, clozapine, darunavir, dasatinib, delavirdine, dexamethasone, diltiazem, doxacurium, erythromycin, felodipine, fesoterodine, fosamprenavir, imatinib, influenza vaccines, lacosamide, lapatinib, levetiracetam, lopinavir, methylprednisolone, midazolam, nelfinavir, nilotinib, piracetam, prednisolone, propoxyphene, ritonavir, rivaroxaban, rufinamide, solifenacin, St John s wort, telithromycin, temsirolimus, terbinafine, tolvaptan, troleandomycin, verapamil, voriconazole... 

Clinically important, potentially hazardous interactions with amprenavir, atazanavir, clarithromycin, delavirdine, grapefruit juice, indinavir, itraconazole, ketoconazole, nefazodone, ritonavir, saquinavir, telithromycin, voriconazole... 

Clinically important, potentially hazardous interactions with amiodarone, astemizole, bepridil, carbamazepine, chloroquine, cisapride, clarithromycin, dihydroergotamine, disopyramide, ergotamine, grapefruit juice, halofantrine, haloperidol, itraconazole, ketoconazole, methadone, moxifloxacin, phenobarbital, phenytoin, pimozide, procainamide, quinidine, rifampicin, ritonavir, sotalol, St John s wort, telithromycin, terfenadine, voriconazole... 

Clinically important, potentially hazardous interactions with amiodarone, anisindione, anticoagulants, azithromycin, corticosteroids, cyclosporine, dapsone, delavirdine, dicumarol, fosamprenavir, lapatinib, lopinavir, midazolam, oral contraceptives, ritonavir, solifenacin, tacrolimus, temsirolimus, tolvaptan, voriconazole... 

Clinically important, potentially hazardous interactions with amiodarone, amprenavir, anisindione, antacids, anticoagulants, aprepitant, atazanavir, atovaquone, beclomethasone, buprenorphine, corticosteroids, cortisone, cyclosporine, cyproterone, dabigatran, dapsone, darunavir, delavirdine, dexamethasone, dicumarol, digoxin, eszopiclone, flunisolide, fosamprenavir, gadoxetate, gestrinone, halothane, imatinib, isoniazid, itraconazole, ketoconazole, lapatinib, lorcainide, methylprednisolone, midazolam, nelfinavir, nifedipine, oral contraceptives, phenylbutazone, prednisone, protease inhibitors, pyrazinamide, ramelteon, ritonavir, saquinavir, solifenacin, sunitinib, tacrolimus, telithromycin, temsirolimus, tipranavir, tolvaptan, trabectedin, triamcinolone, triazolam, voriconazole, warfarin, zaleplon... 

Coadministration with rifampin, rifabutin, or ritonavir is contraindicated because of accelerated voriconazole metabolism. Efavirenz and perhaps other normucleoside reverse transcriptase inhibitors (NNRTIs) significantly increase voriconazole metabolism and slow the metabolism of the NNRTI. When given with phenytoin, the voriconazole dose should be doubled. Drugs that significantly accumulate in patients receiving voriconazole include cyclosporine,... 

The AUC of erlotinib has been found to be increased by 66% when given with ketoconazole 200 mg twice daily for 5 days. The manufacturers advise caution with concurrent use, and recommend that the dose of erlotinib should be reduced if severe adverse reactions occur when given with strong CYP3A4 inhibitors. They specifically name atazanavir, clarithromycin, erythromycin, grapefruit and grapefruit juice, indinavir, itraconazole, ketoconazole, nefazodone, neltinavir, ritonavir, saquinavir, telithromycin, troleandomycin and voriconazole. ... 

The manufacturers of voriconazole say that the concurrent use of ritonavir (at doses of400 mg and above twice daily) is contraindicated, presumably because the efficacy of the voriconazole is expected to be markedly reduced. The manufacturer of ritonavir also recommends that when it is used as a pharmacokinetic enhancer (usually 100 mg twice daily) voriconazole should only be given if the benefits outweigh the risks. Most protease inhibitors are given with ritonavir as a pharmacokinetic enhancer however, caution is also warranted if they are given alone, as all the protease inhibitors can inhibit CYP3A4 to some extent and may therefore also increase voriconazole levels. Voriconazole may also affect protease inhibitor levels, but other than ritonavir and indinavir, which are not affected this does not appear to have been studied. Be aware that some increase in their levels is theoretically possible if voriconazole is given. 

Aouri M, Decosterd LA, Buclin T, Hirschel B, Calmy A, livio F. Drug interactions between voriconazole, darunavir/ritonavir and etravirine in an HIV-infected patient with Aspergillus pneumonia. AIDS 2012 26(6) 776-8. 

---