Terfenadine ketoconazole

Asternizole, terfenadine Ketoconazole, erythromycin, etc. CYP3A4 Ventricular, arrhythmia... 

Honig PK, Wortham DC, Zamani K, et al. Terfenadine-ketoconazole interaction. Pharmacokinetic and electrocardiographic consequences. JAMA 1993 269 1513-1518. 

Jurima-Romet, M. Crawford, K. Cyr, T. Inaba, T. Terfenadine metabolism in human liver. In vitro inhibition by macrolide antibiotics and azole antifungals. Drug Metab.Dispos., 1994, 22, 849—857 [extracted metabolites microsomal incubations rat column temp 35 LOQ 92 nM] von Moltke, L.L. Greenblatt, D.J. Duan, S.X. Harmatz, J.S. Shader, R.I. In vitro prediction of the terfenadine-ketoconazole pharmacokinetic interaction. J.Clin.Pharmacol., 1994, 34, 1222—1227 [clomipramine (IS) microsomal incubations]... 

CYP3A4 is highly inducible by a large variety of commonly prescribed and utilized synthetic drugs (e.g., carbamazepine) and plant products (e.g., St. John s wort) (Roby, Anderson et al, 2000), and at the same time also is potently inhibited by various other medications (e.g., terfenadine and ketoconazole) (Jurima-Romet, Crawford etal, 1994) as well as common foodstuffs (e.g., grapefruit juice) (Oesterheld 8c Kallepalli, 1997). Since individual and ethnic/cultural groups vary dramatically in their exposure to these inducers and inhibitors, it stands to reason that... 

In 1990 torsades de pointes was reported in a patient who had received both terfenadine and ketoconazole. Terfenadine is almost completely converted to an active metabolite in the liver. In patients with severe liver disease or those taking drugs that... 

Androgens, estrogens, erythromycins, terfenadine, cyclosporine, dapsone, ketoconazole,... 

Burkhart GA, Sevka Ml, Temple R, Honig PK. Temporal decline in filling prescriptions for terfenadine closely in time with those for either ketoconazole or erythromycin. Clin Pharmacol Ther 1997 61(l) 93-96. 

Contraindications Hypersensitivity to ketoconazole Concurrent use of terfenadine or astemizole... 

Figure 5.3d The metabolism of the drug terfenadine. The double lines indicate the inhibition of metabolism by other drugs such as ketoconazole or the natural product found in grapefruit juice. This leads to a rise in the blood level of the drug and toxicity.

T effects OF amiodarone, astemizole, atorvastadn, barbiturates, bepridil, bupropion, cerivastatin, cisapride, clorazepate, clozapine, clarithromycin, desipramine, diazepam, encainide, ergot alkaloids, estazolam, flecainide, flurazepam, indinavir, ketoconazole, lovastatin, meperidine, midazolam, nelfinavir, phenytoin, pimozide, piroxicam, propafenone, propoxyphene, quinidine, rifabutin, saquinavir, sildenafil, simvastatin, SSRIs, TCAs, terfenadine, triazolam, troleandomycin, zolpidem X effects W/ barbiturates, carbamazepine, phenytoin, rifabutin, rifampin, St. John s wort, tobacco X effects OF didanosine, hypnotics, methadone, OCPs, sedatives, theophylline, warfarin EMS T Effects of amiodarone, diazepam, midazolam and BBs, may need X- doses concurrent use of Viagra-type drugs can lead to hypotension X- effects of warfarin concurrent EtOH use can T adverse effects T glucose ODs May cause an extension of adverse SEs symptomatic and supportive Rivasrigmine (Exelon) [Cholinesterase Inhibitor/Anri ... 

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