Drug Interactions
Ritonavir interacts with many medications. Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop or change the dosage of any medicine before checking with your doctor or pharmacist first. This drug should not be used with the following medications because very serious interactions may occur: alfuzosin, certain antiarrhythmics (amiodarone, flecainide, propafenone, quinidine), certain benzodiazepines (midazolam, triazolam), bosentan, conivaptan, disulfiram, eletriptan, ergot alkaloids (such as dihydroergotamine, ergonovine, ergotamine, methylergonovine), pimozide, ranolazine, certain "statin" cholesterol drugs (simvastatin, lovastatin), St John's wort, voriconazole. If you are currently using any of these medications listed above, tell your doctor or pharmacist before starting ritonavir. Other medications can affect the removal of ritonavir from your body, which may affect how ritonavir works. Examples include rifampin, other HIV drugs (such as delavirdine), among others. Ritonavir can slow down or speed up the removal of other medications from your body, which may affect how they work. Examples of affected drugs include digoxin, theophylline, warfarin, certain antiarrhythmics (including disopyramide, mexiletine), antidepressants (such as bupropion, fluoxetine, nefazodone, trazodone), certain beta blockers (metoprolol, timolol), calcium channel blockers (such as nifedipine, felodipine), some cancer drugs (such as dasatinib, sunitinib, vincristine), certain azole fungal medications (ketoconazole, itraconazole), other HIV drugs (including atazanavir, saquinavir, didanosine, maraviroc), anti-seizure drugs (including carbamazepine, phenytoin), drugs to treat erectile dysfunction/pulmonary hypertension (such as sildenafil, vardenafil), certain "statin" cholesterol drugs (atorvastatin, rosuvastatin), certain narcotic pain medications (methadone, meperidine, propoxyphene), among others. If any of these medications are taken with ritonavir, your doctor may change your dose of ritonavir or the other drug(s), or your doctor may monitor you specially. Consult your doctor or pharmacist for more details. This medication may decrease the effectiveness of some birth control pills. This can result in pregnancy. However, to reduce the risk of spreading HIV to others, always use barrier protections during all sexual activity. (See also Notes section.) This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.