Rifabutin Nevirapine

Drugs that may affect nelfinavir include anticonvulsants, azithromycin, azole antifungals, efavirenz, delavirdine, HMG-CoA reductase inhibitors, indinavir, interleukins, nevirapine, rifabutin, rifampin, ritonavir, saquinavir, St. John s wort. Drugs that may be affected by nelfinavir include amiodarone, antiarrhythmics (amiodarone, quinidine), azithromycin, benzodiazepines, efavirenz, ergot alkaloids, delavirdine, didanosine, fentanyl, indinavir, lamivudine methadone, nonsedating antihistamines, oral contraceptives, phenytoin, pimozide, quinidine, rifabutin, saquinavir, sildenafil, sirolimus, tacrolimus, zidovudine. 

Rifampin Daily for 4 months For persons who are contacts of patients with isoniazid-resistant rifampin susceptible TB. In HIV-infected patients, protease inhibitors or NNRTIs generally should not be administered concurrently with rifampin rifabutin can be used as an alternative for patients treated with indinavir, nelfinavir, amprenivir, ritonavir, orefavirenz, and possibly with nevirapine or soft-gel saquinavir5 B (II) B (III)... 

Drugs that might decrease plasma concentrations of lopinavir/ritonavir include rifampin, phenobarbital, carbamazepine, phenytoin, azole antifungals, delavirdine, rifabutin, St. John s wort, efavirenz, nevirapine, and corticosteroids. 

Drugs that may affect nevirapine include rifamycins (eg, rifampin, rifabutin), fluconazole, St. John s wort. 

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... 

Nevirapine induces and is metabolized by CYP3A4 therefore, coadministration of drugs that induce or are metabolized by this isoenzyme may result in interactions. Nevirapine may decrease the effectiveness of ethinyl estradiol-based contraceptives and can lower plasma concentrations of methadone. Nevirapine should not be administered with ketoconazole, rifampin, or rifabutin. 

HIV infection (in combination with other antiretrovirals) PO 800 mg (two 400-mg capsules) q8h. Dosage adjustments when given concomitantly Delavirdine, itraconazole, ketoconazok Reduce dose to 600 mg q8h. Efavirenz-. Increase dose to 1,000 mg q8h. Lopinavir/ritonavir Reduce dose to 600 mg twice a day. Nevirapine-. Increase dose to 1,000 mgqSh. Rifabutin-. Reduce rifabutin by lA and increase indinavir to 1,000 mg q8h. Ritonavir 100-200 mg twice a day and indinavir 800 mg twice a day or ritonavir 400 mg twice a day and indinavir 400 mg twice a day. 

Nevirapine is a moderate inducer of CYP3A metabolism, resulting in decreased levels of amprenavir, indinavir, lopinavir, saquinavir, efavirenz, and methadone (Table 49-4). Drugs that induce the CYP3A system, such as tipranavir, rifampin, rifabutin, and St. John s wort, can decrease levels of nevirapine, whereas those that inhibit CYP3A activity, such as fluconazole, ketoconazole, and clarithromycin, can increase nevirapine levels. 

Lopinavir/Ritonavir (Kaletra) [Anrirelroviral/Protease Inhibitor] Uses HIV Infxn Action Protease inhibitor Dose Adults. Tx naive 2 tab PO daily or 1 tab PO bid Tx experiencedpt 1 tab PO bid (T dose if w/ amprenavir, efavirenz, fosamprenavir, nelfinavir, nevirapine) Peds. 7-15 kg 12/3 mg/kg PO bid 15-40 kg 10/2.5 mg/kg PO bid >40 kg Adult dose w/ food Caution [C, /-] Numerous interactions Contra w/drugs dependent on CYP3A/CYP2D6 (Table VI-8) Disp Tab, soln SE Avoid disulfiram (soln has EtOH), metronidazole GI upset, asthenia, T cholesterol/triglycerides, pancreatitis protease metabolic synd Interactions T Effects Wl clarithromycin, erythromycin T effects OF amiodarone, amprenavir, azole andfungals, bepridil, cisapride, cyclosporine, CCBs, ergot alkaloids, flecainide, flurazepam, HMG-CoA reductase inhibitors, indinavir, lidocaine, meperidine, midazolam, pimozide, propafenone, propoxyphene, quinidine, rifabutin, saquinavir, sildenafil, tacrolimus, terfenadine, triazolam, zolpidem 1 effects Wl barbiturates, carbamazepine, dexamethasone, didanosine, efavirenz, nevirapine, phenytoin, rifabutin, rifampin, St. John s wort 1 effects OF OCPs, warfarin EMS Use andarrhythmics and benzodiazepines... 

Carbamazepine, dexamethasone, efavirenz, nevirapine, phenytoin, rifabutin, rifampin may decrease caspofungin levels... 

MODAFINIL 1. ANTIBIOTICS-rifabutin 2. ANTICANCER AND IMMUNOMODULATING DRUGS - corticosteroids 3. ANTIDEPRESSANTS-St John s wort 4. ANTIEPILEPTICS -phenytoin 5. ANTIDIABETIC DRUGS-pioglitazone 6. ANTIVIRALS - efavirenz, nevirapine May 1 modafinil levels Induction of CYP3A4, which has a partial role in the metabolism of modafinil Be aware... 

Clinically important, potentially hazardous interactions with amprenavir, aprepitant, atazanavir, carbamazepine, chlorpheniramine, cimetidine, clarithromycin, clorazepate, CNS depressants, darunavir, delavirdine, dexamethasone, efavirenz, erythromycin, esomeprazole, fluconazole, fluoxetine, fosamprenavir, grapefruit juice, griseofulvin, imatinib, indinavir, itraconazole, ivermectin, ketoconazole, lopinavir, nelfinavir, nevirapine, phenobarbital, phenytoin, primidone, rifabutin, rifampin, ritonavir, roxithromycin, saquinavir, St John s wort, telithromycin, tipranavir... 

Nevirapine Efavirenz increase needed if given with rifabutin. 

Carbamazepine, dexamethasone, glutethimide, nevirapine, phenobarbital, phenytoin, pregnenolone-16a-carbonitrile, progesterone, rifabutin, rifampin, ritonavir, St. John s Wort, sulfadimidine, sulfinpyrazone, troglitazone, troleandomycin... 

Indinavir raises rifabutin concentrations and increases rifabntin toxicity the rifabutin daily dose, therefore, should be reduced by 50%. Drugs that induce CYP3A4 may lower indinavir concentrations and should be avoided. Rifampin lowers the indinavir AUC by 90% and is contraindicated efavirenz, nevirapine, and rifabutin lower indinavir levels less snbstantially (by 25% to 35%) and may necessitate an increased indinavir dose. 

The manufacturers report that carbamazepine reduced the mean maximum plasma concentration and AUC of aripiprazole 30 mg by 68% and 73%, respectively. They recommend that the dose of aripiprazole is doubled when taken with carbamazepine. Other potent inducers of CYP3A4, such as efavirenz, nevirapine, phenytoin, phenobarbital, primidone, rifabutin, rifampicin and St John s wort are expected to have similar effects and an increase in the dose of aripiprazole may also be necessary if these drugs are given. ... 

Rifabutin and rifampicin (rifampin) cause a very marked fall in delavirdine plasma levels rifabutin levels are raised when the delavirdine dose is increased to compensate for this. Rifabutin does not affect efavirenz levels, whereas efavirenz decreases rifabutin levels. There is usually no important interaction between rifabutin and nevirapine, although some patients may have a higher risk of rifabutin adverse effects. 

Rifabutin. In one study, the pharmacokinetics of nevirapine were only minimally affected by rifabutin in 19 patients, when compared with historical data. The manufacturer notes that the concurrent use of rifabutin with nevirapine caused a minor 9% increase in nevirapine clearance and a 17% increase in its AUC, and a 28% increase in maximum steady-state rifabutin levels. They say that because of the high intersubject variability, some patients may experience large increases in rifabutin exposure and may be at higher risk of adverse effects. Concurrent use should be well monitored and undertaken cautiously. The CDC in the US state that the combination of nevirapine and rifabutin can be used. ... 

Rifampicin (Rifampin). The manufacturer states that the AUC of nevirapine was reduced by 58% by rifampicin in 14 subjecls, when compared with historical data. There was no change in steady-state rifampicin pharmacokinetics. Based on these pharmacokinetic data, the manufacturer suggests that the concurrent use of rifampicin with nevirapine is not recommended, and that rifabutin may be considered instead, with close monitoring of adverse effects. ... 

Maldonado S, LamsonM, Gigliotti M, Pav JW, Robinson P. Pharmacokinetic interaction between nevirapine and rifabutin. Intersci Conf Antimicrob Agents Chemother 999) 39, 21. 

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