Simvastatin 4- Itraconazole

E. Simvastatin. Itraconazole inhibits cytochrome P450 3A4. This cytochrome is responsible for metabolism of simvastatin. Therefore, itraconazole can increase serum level of simvastatin and increase its toxicity. 

Simvastatin Itraconazole — Increase in AUC of total simvastatin (18.6-fold)... 

Drugs that may affect repaglinide include CYP 450 inhibitors (eg, clarithromycin, erythromycin, ketoconazole, miconazole), CYP 450 inducers (eg, barbiturates, carbamazepine, rifampin), beta blockers, calcium channel blockers, chloramphenicol, corticosteroids, coumarins, estrogens, gemfibrozil, isoniazid, itraconazole, levonorgestrel and ethinyl estradiol, MAOIs, nicotinic acid, NSAIDs, oral contraceptives, phenothiazines, phenytoin, probenecid, salicylates, simvastatin, sulfonamides, sympathomimetics, thiazides and other diuretics, and thyroid products. 

Ezetimibe/Simvastatin (Vytorin) [Antilipemic/HMG CoA Reductose Inhibitor] Uses H rp cholest olemia Action X Absorption of cholesterol phytost ol w/ HMG-CoA reductase inhibitor Dose 10/10-10/80 mg/d PO w/ cyclosporine or danazol 10/10 mg/d max w/ amio-darone or verapamil 10/20 mg/d max -1- w/ sev e renal insuff Caution [X, -] w/ CYP3A4 inhibitors (Table VI-8), gemfibrozil, niacin >lg/d, danazol, amiodarone, verapamil Contra PRG/lactation livCT Dz, t LFTs Disp Tabs SE HA, GI upset, myalgia, myopathy (muscle pain, weakness, or tendOTiess w/ CK 10 x ULN, rhab-domyolysis), Hep, Infxn Interactions t Risk of myopathy W7 clarithromycin, erythromycin, itraconazole, ketoconazole EMS None OD Sxs unknown symptomatic and supportive... 

Itraconazole Alfentanil, alprazolam, astemizole, atorvastatin, buspirone, cisapride, cyclosporine, delavirdine, diazepam, digoxin, felodipine, indinavir, loratadine, lovastatin, midazolam, nisoldipine, phenytoin, quinidine, ritonavir, saquinavir, sildenafil, simvastatin, sirolimus, tacrolimus, triazolam, verapamil, warfarin... 

Physicians should check for lipid-lowering drugs before treating elderly individuals with itraconazole (73). Susceptibility to this interaction varies from statin to statin, in that simvastatin is more affected than pravastatin (74). Concomitant use of simvastatin with itraconazole should be avoided, and the same holds true for atorvastatin (75). In another study, the blood concentration of fluvastatin was not significantly increased, whereas that of lovastatin was (76). 

Neuvonen PJ, Kantola T, Kivisto KT. Simvastatin but not pravastatin is very susceptible to interaction with the CYP3A4 inhibitor itraconazole. Clin Pharmacol Ther 1998 63(3) 332-41. 

Itraconazole probably inhibits simvastatin metabolism (SEDA 21, 459). 

The effects of itraconazole 200 mg on the pharmacokinetics of simvastatin have been studied in a randomized, double-blind, crossover study in 10 healthy volunteers (47). Itraconazole increased the Cmax and AUC of simvastatin and... 

In two cases, rhabdomyolysis was caused by itraconazole in heart transplant recipients taking long-term ciclosporin and simvastatin (48,49). To avoid severe myopathy, ciclosporin concentrations should be monitored frequently and statins should be withdrawn or the dosage should be reduced, as long as azoles need to be prescribed in transplant recipients. Patients need to be educated about signs and symptoms that require immediate physician intervention. 

Vlahakos DV, Manginas A, Chilidou D, Zamanika C, Alivizatos PA. Itraconazole-induced rhabdomyolysis and acute renal failure in a heart transplant recipient treated with simvastatin and cyclosporine. Transplantation 2002 73(12) 1962-4. 

Maxa JL, Melton LB, Ogu CC, Sills MN, Limanni A. Rhabdomyolysis after concomitant use of cyclosporine, simvastatin, gemfibrozil, and itraconazole. Ann Pharmacother 2002 36(5) 820-3. 

A4/3A5 Midazolam, buspirone, felodipine, lovastatin, eletriptan, sildenafil, simvastatin, triazolam Atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin Rifampin, carbamazepine... 

CYP3A4 Inhibition Amiodarone, clarithromycin, erythromycin, cimetidine, cyclosporine, fluoxetine fluvoxamine, itraconazole, ketoconazole, nefazodone, verapamil, diltiazem HIV antivirals delaviridine, indanavire, nelfmavire, ritonavire, sequinavire Atorvastatin Lovastatin Simvastatin ... 

Ishigam M, Uchiyama M, Kondo T, Iwabuchi H, Inoue S, Takasaki W, Ikeda T, Komai T, Ito K, Sugiyama Y. 2001. Inhibition of in vitro metabolism of simvastatin by itraconazole in humans and prediction of in vivo drug-drug interactions. Pharm Res 18 622-631. 

Itraconazole increases the risk of skeletal muscle toxicity of some statins by increasing their serum concentrations, but not all statins are equally affected. Concomitant use of atorvastatin, lovastatin, and simvastatin with itraconazole should be avoided or the doses should be reduced fluvastatin and pravastatin have much less potential than other statins for chnically significant interactions with itraconazole and other CYP3A4 inhibitors the effects of cerivastatin are intermediate. 

E Itraconazole. Imatinib is primarily metabolized by the CYP3A4 hepatic enzyme system. Drugs that may inhibit this enzyme (such as ketoconazole, itraconazole, erythromycin, clarithromycin, etc.) may impair clearance of imatinib and result in increased toxicity. Imatinib itself is also a fairly potent inhibitor of the CYP3A4 enzyme and may result in toxicity due to other drugs that are substrates for this enzyme (such as simvastatin, warfarin, benzodiazepines, etc.). The other medications iisted are uniikeiy to affect the function of 0 P3A4 or interact adversely with imatinib. 

Clinically important, potentially hazardous interactions with astemizole, atorvastatin, cyclosporine, fluvastatin, glibenclamide, glyburide, itraconazole, ketoconazole, lovastatin, oral contraceptives, reboxetine, simvastatin, St John s wort,... 

Clinically important, potentially hazardous interactions with alfentanil, aminophylline, amisulpride, amoxicillin, ampicillin, anticonvulsants, astemizole, atorvastatin, benzodiazepines, bromocriptine, buprenorphine, bupropion, carbamazepine, cilostazol, ciprofloxacin, cisapride, clindamycin, colchicine, cyclosporine, dasatinib, digoxin, dihydroergotamine, diltiazem, disopyramide, enoxacin, eplerenone, ergotamine, eszopiclone, everolimus, fluconazole, fluoxetine, fluvastatin, gatifloxacin, HMG-CoA reductase inhibitors, imatinib, itraconazole, ketoconazole, lomefloxacin, lorazepam, lovastatin, methadone, methylprednisolone, methysergide, midazolam, mizolastine, moxifloxacin, nitrazepam, norfloxacin, ofloxacin, paroxetine, pimozide, pravastatin, quinolones, ranolazine, repaglinide, rupatadine, sertraline, sildenafil, simvastatin, sparfloxacin, sulpiride, tacrolimus, terfenadine, triazolam, troleandomycin, vardenafil, verapamil, vinblastine, warfarin, zaleplon, zolpidem, zuclopenthixol... 

Clinically important, potentially hazardous interactions with amlodipine, anisindione, anticoagulants, aprepitant, atorvastatin, barbiturates, benzodiazepines, butabarbital, carbamazepine, chlordiazepoxide, clarithromycin, clonazepam, dorazepate, corticosteroids, cyclosporine, dexamethasone, diazepam, dicumarol, erythromycin, ethotoin, felodipine, flurazepam, fluvastatin, fosphenytoin, isradipine, itraconazole, ketoconazole, lorazepam, lovastatin, mephenytoin, mephobarbital, midazolam, nicardipine, nifedipine, nimodipine, nisoldipine, oxazepam, pentobarbital, phenobarbital, pimozide, pravastatin, primidone, quazepam, rifampin, secobarbital, simvastatin, St John s wort, temazepam, warfarin... 

Clinically important, potentially hazardous interactions with abacavir, atorvastatin, bepridil, bupropion, carbamazepine, clarithromycin, cyclosporine, dexamethasone, digoxin, felodipine, fluticasone propionate, fosamprenavir, itraconazole, ketoconazole, lovastatin, methadone, midazolam, nicardipine, nifedipine, phenobarbital, phenytoin, rifabutin, simvastatin, sirolimus, St John s wort, systemic lidocaine, tacrolimus, tenofovir, trazodone, vinblastine, vincristine, voriconazole, warfarin, zidovudine... 

Figure 11.9 Different effects of itraconazole and obtained from the previous literature. The details cyclosporin A on the plasma AUC of pravastatin, are described in the Section 11.7.1. BA simvastatin, and atorvastatin [210, 221-224], bioavailability, Fa Fg fraction of dose absorbed The fold-increase in the plasma AUC of statins from the small intestine to the portal vein, Fh was expressed after coadministration of hepatic availability,...

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