Omeprazole Erythromycin

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... 

Antibiotics clarithromycin, erythromycin Others omeprazole, cisapride, dapsone, lavastatin... 

Drugs that may affect HMG-CoA reductase inhibitors include alcohol, amiodarone, antacids, azole antifungals, bile acid sequestrants, cimetidine, cyclosporine, diltiazem, erythromycin, gemfibrozil, isradipine, nefazodone, niacin, nicotinic acid, omeprazole, phenytoin, propranolol, protease inhibitors, ranitidine, rifampin, St. John s wort, and verapamil. 

Drugs that may affect tacrolimus include nephrotoxic agents (aminoglycosides, amphotericin B, cisplatin, cyclosporine), antifungals, bromocriptine, calcium channel blockers, cimetidine, clarithromycin, danazol, diltiazem, erythromycin, methylprednisolone, metoclopramide, carbamazepine, phenobarbital, phenytoin, rifamycins, cisapride, chloramphenicol, metronidazole, nefazodone, omeprazole, protease inhibitors, macrolide antibiotics, fosphenytoin, and St. John s wort. 

Tateishi, T., Graham, S. G., Krivoruk, Y., and Wood, A. J. J. (1995) Omeprazole does not affect measured CYP3A4 activity using the erythromycin breath test. Bn J. Clin. Pharmacol. 40, 411-412. 

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. 

Drug Interactions Gemfibrozil Niacin Erythromycin Cholestyramine Digoxin Cimetidine/ranitidine/ omeprazole Rifampicin Warfarin Itraconazole Gemfibrozil Niacin Erythromycin Propranolol Digoxin Warfarin Antacids Colestipol Digoxin Erythromycin Oral contraceptives Fibrates Niacin Azole antifungals... 

The most used and validated probe drugs for C YP3 A phenotyping are midazolam and 14C-erythromycin (Watkins 1994). Alfentanyl, alprazolam, dapsone, dextromethorphan, lidocaine. nifedipine, omeprazole, quinine, verapamil have also been used but less frequently, and CYP3A specificity for some of them has been questioned. The endogenous 6(->-hydroxycortisol test (measurement of 6 3-hydroxycortisol cortisol ratio in urine) is only useful for detecting CYP3A induction, and may be influenced by renal CYP3 A activity. 

Omeprazole, like cimetidine, can impair benzodiazepine metabolism and lead to adverse effects (SEDA-18, 43). Other drugs, including antibiotics (erythromycin, chloramphenicol, isoniazid), antifungal drugs (ketoconazole, itraconazole, and analogues), some SSRIs (fluoxetine, paroxetine), other antidepressants (nefazodone), protease inhibitors (saquinavir), opioids (fentanyl), calcium channel blockers (diltiazem, verapamil), and disulfiram also compete for hepatic oxidative pathways that metabolize most benzodiazepines, as well as zolpidem, zopiclone, and buspirone (SEDA-22,39) (SEDA-22,41). 

Examples of commercial enteric-coated formulations include Ery-Tab (erythromycin Abbott), Prilosec (omeprazole Astra Merck), Pancrease ... 

Polyvinyl acetate phthalate reacts with povidone to form an insoluble complex that precipitates out of solution benzo-caine is also incompatible with polyvinyl acetate phthalate. Erythromycin disperses in polyvinyl acetate phthalate and has been shown to be physically stable while omeprazole exists in the amorphous form in polyvinyl acetate phthalate coatings with no evidence of interaction. ... 

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... 

Clarithromycin is an H. pylori agent/macrolide, which inhibits microbial protein synthesis. Clarithromycin is indicated in the treatment of infections of the respiratory tract, skin and skin structure treatment of disseminated atypical mycobacterial infections caused by susceptible strains of specific microorganisms and prevention of disseminated Mycobacterium avium complex disease in patients with advanced HIV infection. Clarithromycin in combination with omeprazole is indicated in the treatment of patients with an active duodenal ulcer associated with H. pylori infection. In children it is used in acute otitis media. Macrolides are erythromycin, clarithromycin, and azithromycin. 

CYP3A4 Amitryptiline, Imipramin, Cyclosporine, Docetaxel, Epipodophyllotoxin, Erythromycin, Losartan, Diazepam, Carbamazepine, Nefadozone, Nifedipine, Omeprazole, Terfenadine, Chlorpyrifos (Insecticide), Testosterone, Estradiol, Progesterone, and synthetic sexual steroids... 

The case of pseudomembranous colitis and cholestatic jaundice in one patient was attributed to the combination of docetaxel and doxorubicin, but the patient was also receiving long-term treatment with erythromycin and omeprazole which may have contributed to the interaction by inhibiting docetaxel metabolism by the cytochrome P450 isoenzyme CYPSA." ... 

Clarithromycin approximately doubles the serum levels of esomeprazole, lansoprazole and omeprazole, but has no effect on panto-prazole. A small rise in the serum levels of clarithromycin might also occur, which may be therapeutically useful. Some very limited evidence indicates that erythromycin raises serum omeprazole... 

A study was undertaken in a patient to confirm the in vitro findings that erythromycin inhibits the metabolism of omeprazole. After taking 500 mg of erythromycin base and 20 mg of omeprazole daily for 8 weeks, it was found that the AUC of omeprazole was increased almost fourfold, and the metabolite of omeprazole was undetectable. These raised omeprazole levels might have been expected to increase its effectiveness, but in this patient the time during which gastric pH was less than 4 decreased by 22%. ... 

The pharmacokinetic interactions between clarithromycin and omeprazole, esomeprazole and lansoprazole are established. However, none of the changes reported represents an adverse interaction, but they may help to explain why concurrent use is valuable in the eradication of Helicobacter pylori. Erythromycin is likely to interact similarly, whereas roxithromycin does not. Pantoprazole is not affected by macrolides. 

Salcedo JA, Benjamin SB, Maher KA, Sukhova N. Erythromycin inhibits the metabolism of omeprazole. Gastroenterology (1997) 112 (4 SuppI), A277. 

Several active substances are unstable in an acidic environment and will degrade when in contact with gastric juice. Examples are omeprazole, pantoprazole, erythromycin and pancreatic enzymes. Such active substances are formulated in a tablet or pellets covered with an acid-resistant layer, a so-called enteric coating. The acidic nature of the polymers used in these coatings prevents dissolution in the gastric environment. The coating will dissolve in the small intestine (with higher pH values), after which the active substance is released. Alternatively, the active substance may be used in... 

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