4- Erythromycin Fluconazole

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... 

Intermittent claudication PO 100 mg twice a day at least 30 min before or 2 hr after meals. 50 mg twice a day during concurrent therapy with clarithromycin, diltiazem, erythromycin, fluconazole, fluoxetine, omeprazole, or sertraline. 

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. 

A Atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin Amprenavir, aprepitant, diltiazem, erythromycin, fluconazole, fosamprenavir, grapefruit juice", verapamil Cimetidine... 

Antimicrobials. Aztreonam, cefamandole, chloramphenicol, ciprofloxacin, co-trimoxazole, erythromycin, fluconazole, itraconazole, ketoconazole, metronidazole, miconazole, ofloxacin and sulphonamides (including co-trimoxazole) increase anticoagulant effect by mechanisms that include interference with warfarin or vitamin K metabolism. Rifampicin and griseofulvin accelerate warfarin metabolism (enzyme induction) and reduce its effect. Intensive broad-spectrum antimicrobials, e.g. eradication regimens for Helicobacter pylori (see p. 630), may increase sensitivity to warfarin by reducing the intestinal flora that produce vitamin K. 

Clinically important, potentially hazardous interactions with amiodarone, azithromycin, bepredil, bosentan, bretylium, cisapride, clarithromycin, disopyramide, erythromycin, erythromycin fluconazole, fluoxetine, fluvoxamine, grapefruit juice, indinavir, itraconazole, ketoconazole, metronidazole, miconazole, nefazodone, nilotinib, paroxetine, pimozide, probucol, procainamide, quinidine, quinine, ritonavir, saquinavir, sertraline, sotalol, SSRIs, terfenadine, troleandomycin, voriconazole, zileuton, ziprasidone... 

Clinically important, potentially hazardous interactions with ACE inhibitors, angiotensin II receptor antagonist, erythromycin, fluconazole, grapefruit juice, itraconazole, ketoconazole, saquinavir, St John s wort, verapamil... 

In the UK, the manufacturers recommend that the dose of eplerenone should not exceed 25 mg daily in patients taking mild to moderate CYP3A4 inhibitors such as amiodarone, diltiazem, erythromycin, fluconazole, saquinavir and verapamil. In the US, the manufacturer recommends that the starting dose for hypertension should be reduced to 25 mg daily for patients taking these drugs. This seems a sensible precaution. However, note that in many cases erythromycin appears to be a more potent inhibitor of CYP3A4 than clarithromycin (and certainly the other moderate CYP3A4 inhibitors listed above), and so extra caution is probably warranted with this combination. 

Chloral hydrate Chloramphenicol Cimetidine Ciprofloxacin Clofibrate Danazol Disulfiram Doxycycline Erythromycin Fenofibrate Fluconazole Fluorouracil Fluoxetine Fluvoxamine Gemfibrozil Influenza vaccine Isoniazid Itraconazole Fovastatin Metronidazole Miconazole Moxalactam Neomycin Norfloxacin Ofloxacin Omeprazole Phenylbutazone Piroxicam Propafenone Propoyxphene Quinidine Sertraline Sulfamethoxazole Sulfinpyrazone Tamoxifen Testosterone Vitamin E Zafirlukast... 

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. 

For patients receiving weak CYP3A4 inhibitors (eg, erythromycin, saquinavir, verapamil, fluconazole), reduce the starting dose to 25 mg once daily. 

CYP3A4 enzyme. A clinical study has shown that coadministration of eletriptan with ketoconazole, erythromycin, verapamil, and fluconazole increased the Cmax3> cl... 

Because trimetrexate is metabolized by a P450 enzyme system, drugs that induce or inhibit this drug metabolizing enzyme system may elicit important drug interactions that may alter trimetrexate plasma concentrations, which include erythromycin, rifampin, rifabutin, ketoconazole, fluconazole, cimetidine, nitrogen substituted imidazole drugs (eg, clotrimazole, ketoconazole, miconazole). 

Drugs that may increase sirolimus blood concentrations include the following Nicardipine, verapamil, clotrimazole, fluconazole, itraconazole, clarithromycin, erythromycin, troleandomycin, cisapride, metoclopramide, bromocriptine, cimetidine, danazol, HIV-protease inhibitors, cyclosporine, diltiazem, azole antifungals. 

Coadminister known CYP3A4 inhibitors (eg, erythromycin, itraconazole, ketoconazole, fluconazole, calcium channel blockers, cimetidine) with caution in patients with widespread or erythrodermic disease. 

Antibacterials Ciprofloxacin Erythromycin Isoniazid Antidepressants Flnoxetine Huvoxamine Paroxetine Antifungal drugs Fluconazole Itraconazole Ketoconazole Miconazole Antiviral drugs Indinavir Ritonavir Saquinavir Cardiovascular drugs Amiodarone Diltiazem Quinidine Verapamil... 

Hypertension PO 50 mg once a day. If 50 mg once a day produces an inadequate BP response, may increase dosage to 50 mg twice a day. If patient is concurrently receiving erythromycin, saquinavir, verapamil, or fluconazole, reduce initial dose to 25 mg once a day. 

Drugs that have been shown, or would be expected, to increase plasma carbamazepine levels include cimetidine, danazol, diltiazem, macrolides, erythromycin, troleandomycin, clarithromycin, fluoxetine, fluvoxamine, nefazodone, loratadine, terfenadine, isoniazid, niacinamide, nicotinamide, propoxyphene, azoles (e.g., ketaconazole, itraconazole, and fluconazole), acetazolamide, verapamil, grapefruit juice, ... 

Direct hepatocellular injury, e.g. antituberculous drugs (e.g. rifampicin), erythromycin, high-dose penicillins (e.g. flucloxacillin), fluconazole and flucytosine Granulocytopaenia, e.g. high-dose penicillins/cephalosporins Immune thrombocytopaenia/Coombs positive anaemia, e.g. penicillins, cephalosporins... 

Sirolimus is metabolized by CYP2A4 and is a substrate of the P-glycoprotein drug efflux pump drugs like voriconazole, itraconazole, fluconazole and erythromycin increase its blood concentration. Conversely, the inducers of CYP3A4 will decrease blood levels of sirolimus. Cyclosporine increases the bioavailability of sirolimus, possibly due to P-GP inhibition and competition for CYP3A4. The bioavailability is more than 30-40% when the two drugs are administered 4 h apart and is more than... 

Increased risk of QT prolongation with antiarrhythmics, class la and class III, cisapride, phenothiazines, ziprasidone, fluconazole, haloperidol, erythromycin, tacrolimus, tricyclic antidepressants... 

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