Ritonavir Fentanyl

Drugs that may affect amiodarone include hydantoins, cholestyramine, fluoroquinolones, rifamycins, ritonavir, and cimetidine. Drugs that may be affected by amiodarone include anticoagulants, beta-blockers, calcium channel blockers, cyclosporine, dextromethorphan, digoxin, disopyramide, fentanyl, flecainide, hydantoins, lidocaine, methotrexate, procainamide, quinidine, and theophylline. Drug/Lab test interactions Amiodarone alters the results of thyroid function tests, causing an increase in serum T4 and serum reverse T3 levels and a decline in... 

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 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. 

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. 

ALFENTANIL, BUPRENORPHINE, FENTANYL, TRAMADOL PROTEASE INHIBITORS Possibly t adverse effects when buprenorphine is co administered with indinavir, ritonavir (with or without lopinavir) or saquinavir Inhibition of CYP3A4 (CYP2D6 in the case of tramadol) Halve the starting dose and titrate to effect. For single injection of fentanyl, monitor sedation and respiratoiy function closely. If continued use of fentanyl, i dose may be required. Concomitant use of ritonavir and transdermal fentanyl is not recommended... 

Ritonavir is an inhibitor of HIV protease and a potent inhibitor of CYP3A4 and CYP2D6. The interaction between ritonavir and intravenous fentanyl has been investigated in 12 healthy volunteers in a double-blind, placebo-controUed, crossover study (84). The volunteers took ritonavir 600 mg on day 1, ritonavir 900 mg and intravenous fentanyl 5 pg/kg on day 2, and ritonavir 300 mg or placebo on day 3. Ritonavir reduced the clearance of fentanyl by 67% by inhibiting its metabolism. This could result in prolongation of fentanyl-induced respiratory depression in a patient with an aheady compromised cardiorespiratory system. 

Olkkola KT, Palkama VJ, Neuvonen PJ. Ritonavir s role in reducing fentanyl clearance and prolonging its half-life. Anesthesiology 1999 91(3) 681-5. 

By inhibiting CYP3A4, ritonavir can significantly inhibit the metabolism of fentanyl, and considerable cantion is needed (28). 

Clinically important, potentially hazardous interactions with abarelix, acenocoumarol, amisulpride, amprenavir, anisindione, anticoagulants, arsenic, astemizole, carbimazole, celiprolol, ciprofloxacin, dabigatran, degarelix, dicumarol, digoxin, diltiazem, enoxacin, fentanyl, fosamprenavir, gatifloxacin, grapefruit juice, lomefloxacin, methotrexate, moxifloxacin, nilotinib, norfloxacin, ofloxacin, oxprenolol, quinidine, quinolones, rifabutin, rifampin, rifapentine, ritonavir, simvastatin, sparfloxacin, sulpiride, tacrolimus, tipranavir, verapamil, warfarin, zuclopenthixol... 

Clinically important, potentially hazardous interactions with amiodarone, amitriptyline, amoxapine, benzodiazepines, bepridil, clomipramine, clonazepam, clorazepate, delavirdine, desipramine, diazepam, dihydroergotamine, doxepin, ergotamine, fentanyl, flurazepam, imipramine, ixabepilone, lidocaine, lorazepam, methysergide, midazolam, nortriptyline, oxazepam, phenytoin, protriptyline, quazepam, quinidine, rifampin, ritonavir, sildenafil, St John s wort, temazepam, tricyclic antidepressants, trimipramine, vitamin E... 

Clinically important, potentially hazardous interactions with bepridil, cisapride, dasatinib, dofetilide, ergot derivatives, etravirine, fentanyl, fesoterodine, garlic, indinavir, irinotecan, ixabepilone, lapatinib, lovastatin, marihuana, midazolam, pimozide, proton-pump inhibitors, raltegravir, rifampin, ritonavir, sildenafil, simvastatin, solifenacin, St John s wort, temsirolimus, triazolam... 

Acetaminophen, aldrin, alfentanil, amiodarone, aminopyrine, amitriptyline, amprenavir, androstenedione,antipyrine, astemizole, benzphetamine, budesonide, carbamazepine, celecoxib, chlorpromazine, chlorzoxazone, cisapride, clarithromycin, clozapine, cocaine, codeine, cortisol, cyclophosphamide,cyclosporin, dapsone, delavirdine, dextromethorphan, digitoxin, diltiazem, diazepam, erythromycin, 17j3-estradiol, ethinylestradiol, etoposide, felbamate, fentanyl, flutamide, hydroxyarginine, ifosphamide, imipramine, indinavir, ketoconazole, lansoprazole, loratidine, losartan, lovastatin, (iS)"mephen3d in, methadone, mianserin, miconazole, mifepristone, nelfinavir, nevirapine, nicardipine, nifedipine, odansetron, omeprazole, orphenadrine, proguanil, propafenone, quinidine, quinine, rapamycin, retinoic acid, ritonavir, saquinavir, selegiline, serindole, sufentanil, sulfinpyrazone, tacrolimus, tamoxifen, tamsulosin, taxol, teniposide, terfenadine, tetrahydrocannabinol, theophylline, toremifene, triazolam, trimethadone, trimethoprim, troleandomycin, verapamil, warfarin, zatosetron, Zolpidem, zonisamide... 

Ritonavir markedly increases the levels of fentanyl, and markedly increases alfentanil-induced miosis. Other protease inhibitors such as nelfinavir may have a similar effect Care should also be taken if ritonavir is used with other protease inhibitors as a pharmacokinetic enhancer. 

Ritonavir 200 mg increased to 300 mg three times daily for a total of 7 doses increased the AUC of a single 5-mg/kg intravenous dose of fentanyl by 83%, decreased its clearance by 67%, and increased the elimination half-life twofold in healthy subjects. ... 

Both fentanyl and alfentanii ate metabolised by the cytochrome P450 isoenzyme CYP3A4. Ritonavir, and other protease inhibitors, ate potent inhibitors of CYP3A4 and they therefore reduce the metabolism of these opioids, which results in increased levels and effects. 

Noninterfering acetaminophen, albuterol, aspirin, caffeine, clonidine, fentanyl, ibupro-fen, naltrexone, ritonavir... 

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