Ritonavir Clarithromycin

Drugs that may affect indinavir include didanosine, aldesleukin, anticonvulsants, atazanavir, nelfinavir, nevirapine, omeprazole, rifapentine, ritonavir, clarithromycin, azole antifungals, rifamycins, delavirdine, efavirenz, St. John s wort. 

Although the effect of these increases has not been assessed, such marked increases in levels could increase adverse effects. The manufacturers recommend caution when aprepitant is given with ketoconazole and other drugs that are strong inhibitors of CYP3A4. They specifically name ritonavir, clarithromycin, telithromycin, itraconazole, ne-fazodone, troleandomycin, and nelfinavir. For the effect of diltiazem (a moderate CYP3A4 inhibitor), see Calcium-channel blockers + Aprepi-tanf, p. 861. Other inhibitors of CYP3A4 are listed in Table 1.4 , (p.6). 

Azalides azithromycin Azoles fluconazole, itraconazole, ketoconazole, and voriconazole Macrolides erythromycin, clarithromycin Protease inhibitors amprenavir, indinavir, lopinavir/ritonavir, nelfinavir, ritonavir, and saquinavir Quinolones ciprofloxacin, gatifloxacin, levofloxacin, moxifloxacin. 

Sildenafil doses should be decreased when any potent cytochrome P450 3A4 inhibitor is used (e g., cimetidine, erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir, and saquinavir). Vardenafil doses vary accordingto which agent is used (2.5 mg q 72 h for ritonavir, 2.5 mg q 24 h for indinavir, ketoconazole 400 mg daily, and itraconazole 400 mg daily and 5 mg q 24 h for ketoconazole 200 mg daily, itraconazole200 mg daily, and erythromycin). Tadalafil doses are reduced only when it is used with the most potent cytochrome P450 3A4 inhibitors (e g., ketoconazole or ritonavir). 

All patients with the following conditions Serum potassium greater than 5.5 mEq/L at initiation Ccr 30 mL/min or less concomitant use with the following potent CYP3A4 inhibitors Ketoconazole, itraconazole, nefazodone, troleandomycin, clarithromycin, ritonavir, and nelfinavir. 

Coadministration with CYP450 inhibitors- Nhen coadministered with potent CYP3A4 inhibitors (eg, ketoconazole, itraconazole, ritonavir, nelfinavir, clarithromycin, nefazodone), do not exceed a daily dose of darifenacin 7.5 mg. 

Pregnancy (ergotamine s powerful uterine stimulant actions may cause fetal harm) hypersensitivity to ergot alkaloids peripheral vascular disease (eg, thromboangiitis obliterans, leutic arteritis, severe arteriosclerosis, thrombophlebitis, Raynaud s disease) hepatic or renal impairment severe pruritus coronary artery disease hypertension sepsis. The use of potent CYP3A4 inhibitors (ritonavir, nelfinavir, indinavir, erythromycin, clarithromycin, troleandomycin, ketoconazole, itraconazole) with dihydroergotamine is contraindicated. 

Drugs that may affect aprepitant include CYP 3A4 inhibitors (eg, clarithromycin, diltiazem, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, troleandomycin), CYP3A4 inducers (eg, carbamazepine, phenytoin, rifampin), and paroxetine. 

Saquinavir/ritonavir may affect systemic lidocaine, clarithromycin, rifabutin, benzodiazepines, CCBs, FlMGs, cyclosporine tacrolimus, rapamycin, methadone. 

Drugs that may be affected by indinavir include antiarrhythmics, clarithromycin, dihydropyridine calcium channel blockers, HMG-CoA reductase inhibitors, immunosuppressant agents, phosphodiesterase type 5 inhibitors, pimozide, saquinavir, trazodone, cisapride, amiodarone, benzodiazepines, ergot alkaloids, fentanyl, rifamycins, ritonavir. 

Drugs that might affect amprenavir include abacavir, aldesleukin, antacids, anticonvulsants, azole antifungals, clarithromycin, cyclosporine, dexamethasone, buffered didanosine, disulfiram, ethanol, indinavir, methadone, metronidazole, nelfinavir, nonnucleoside reverse transcriptase inhibitors, oral contraceptives, rifamycins, ritonavir, saquinavir, St. John s wort, tacrolimus, and zidovudine. 

Drugs that might be affected by amprenavir include antiarrhythmics, anticonvulsants, azole antifungals, benzodiazepines, calcium channel blockers, cisapride, clarithromycin, cyclosporine, ergot alkaloids, fentanyl, HMG-CoA reductase inhibitors, indinavir, methadone, nelfinavir, oral contraceptives, pimozide, rifabutin, ritonavir, saquinavir, sildenafil, tacrolimus, trazodone, tricyclic antidepressants, warfarin, and zidovudine. 

Drugs that may affect atazanavir include the following antacids and buffered medications, clarithromycin, didanosine (buffered formulation only), efavirenz, H2-receptor antagonists, indinavir, itraconazole, ketoconazole, nevirapine, proton pump inhibitors, rifampin, ritonavir, St. John s wort, tenofovir, voriconazole. 

Drugs that might be affected by lopinavir/ritonavir include ergot derivatives, oral contraceptives, antiarrhythmics, HMG-CoA reductase inhibitors, HIV protease inhibitors, atovaquone, calcium channel blockers, ketoconazole, itraconazole, pimozide, cisapride, clarithromycin, disulfiram, metronidazole, immunosuppressants, midazolam, triazolam, narcotic analgesics, rifabutin and rifabutin metabolite, sildenafil, warfarin, bupropion, clozapine, desipramine, piroxicam, quinidine, theophylline, and zolpidem. 

Drugs that may affect zidovudine include acetaminophen, atovaquone, bone marrow suppressive/cytotoxic agents (eg, adriamycin, dapsone), clarithromycin, doxorubicin, fluconazole, ganciclovir, methadone, nelfinavir/ritonavir, phenytoin, probenecid, ribavirin, rifamycins, stavudine, trimethoprim, and valproic acid. 

St. John s wort, rifamycins, and ritonavir. Drugs that may be affected by efavirenz include phenytoin, phenobarbital, carbamazepine, itraconazole, ketoconazole, methadone, ritonavir, amprenavir, benzodiazepines, clarithromycin, ethinyl estradiol, indinavir, nelfinavir, saquinavir, and warfarin. 

Aprepitant (Emend) [Centrally Acting Antiemetic] Uses Pre-vents N/V assoc w/ emetogenic CA chemo (eg, cisplatin) (use in combo w/ other antiemetics) Action Substance P/neurokinin l(NKi) receptor antagonist Dose 125 mg PO day 1, 1 h before chemo, then 80 mg PO qAM days 2 3 Caution [B, /-] Contra Use w/ pimozide, Disp Caps SE Fatigue, asthenia, hiccups Interactions T Effects W/ clarithromycin, diltiazem, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, troleandomycin T effects OF alprazolam, astem-izole, cisapride, dexamethasone, methylprednisolone, midazolam, pimozide, terfe-nadine, triazolam, chemo agents, eg, docetaxel, etoposide, ifosfamide, imatinib, irinotecan, paclitaxel, vinblastine, vincristine, vinorelbine i effects W/ paroxetine,... 

NA /D, abd pain, bleeding, fevCT, T QT Interactions t Effects W7 atazanavir, clarithromycin, CT5rthromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfi-navir, ritonavir, saquinavir, telithromycin X effects W7 antacids, carbamazqjine, dexamethasone, phenobarbital, phenytoin, rifampicin, St. John s wort EMS Drug contains lactose, may cause D/abd discomfort in pts w/ lactose intolerance OD Sxs unknown symptomatic and supportive... 

Deravirdine (Rescnptor) [Antiretroviral/NNRTI] Uses HIV Infxn Action Nonnucleoside RT inhibitor Dose 400 mg PO tid Caution [C, ] CDC recommends HIV-infected mothers not to breast-feed (transmission risk) w/ renal/hepatic impair Contra Use w/ drugs dependent on CYP3A for clearance (Table VI-8) Disp Tabs SE Fat redistribution, immune reconstitution synd, HA, fatigue, rash, T transaminases, N/V/D Interactions T Effects W/ fluoxetine T effects OF benzodiazepines, cisapride, clarithromycin, dapsone, ergotamine, indinavir, lovastatin, midazolam, nifedipine, quinidine, ritonavir, simvastatin, terfena-dine, triazolam, warfarin effects W/ antacids, barbiturates, carbamazepine, cimetidine, famotidine, lansoprazole, nizatidine, phenobarbital, phenytoin, ranitidine, rifabutin, rifampin effects OF didanosine EMS Use of benzodiazepines and CCBs should be avoided may cause a widespread rash located on upper body and arms OD May cause an extension of nl SEs symptomatic and supportive Deferasirox (Exjade) [Iron Chelator] Uses Chronic iron overload d/t transfusion in pts >2 y Action Oral iron chelator Dose Initial 20 mg/kg... 

Efavirenz (Sustiva) [Antiretroviral/NNRTI] Uses Hiv infxns Action Antiretroviral nonnucleoside RTI Dose Adults. 600 mg/d PO qhs Feds. See package insert avoid high-fat meals Caution [D, ] CDC recommends HIV-infected mothers not breast-feed Contra Component sensitivity Disp Caps SE Somnolence, vivid dreams, dizziness, rash, N/V/D Interactions T Effects W/ ritonavir T effects OF CNS depressants, ergot derivatives, midazolam, ritonavir, simvastatin, triazolam, warfarin X effects W/ carbamazepine, phenobarbital, rifabutin, rifampin, saquinavir, St. John s wort i effects OF amprenavir, carbamazepine, clarithromycin, indinavir, phenobarbital, saquinavir, warfarin may alter effectiveness OF OCPs EMS Concurrent EtOH usage can t CNS d ression OD May cause muscle contractions and adverse CNS effects activated charcoal may be effective... 

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... 

Inhibitors of CYP3A4 such as erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir and grapefruit juice may increase plasma concentrations of estrogens and may result in side effects ... 

Drugs that may inhibit cytochrome P450 metabolism of other drugs include amiodarone, androgens, atazanavir, chloramphenicol, cimetidine, ciprofloxacin, clarithromycin, cyclosporine, delavirdine, diltiazem, diphenhydramine, disulfiram, enoxacin, erythromycin, fluconazole, fluoxetine, fluvoxamine, furanocoumarins (substances in grapefruit juice), indinavir, isoniazid, itraconazole, ketoconazole, metronidazole, mexile-tine, miconazole, nefazodone, omeprazole, paroxetine, propoxyphene, quinidine, ritonavir, sulfamethizole, verapamil, voriconazole, zafirlukast, and zileuton. 

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