Omeprazole Warfarin

C8 C9 C18 C19 C58P C62P Taxol (C8), NSAIDS, warfarin (C9), omeprazole (C19)... 

While generally not of major concern, omeprazole may inhibit the metabolism of warfarin, diazepam, and phenytoin lansoprazole may decrease theophylline concentrations. Drug interactions with omeprazole are of particular concern in patients who are considered slow metabolizers, as are approximately 3% of the Caucasian population. Unfortunately, it is unclear which patients have the polymorphic gene variation that makes them slow metabolizers.17 The metabolism of esomeprazole may also be altered in patients with this polymorphic gene variation. Patients on potentially interacting drugs should be monitored for development of drug-related problems. 

Decreased cigarette consumption in smokers, easier to stop smoking Exaggerated response to warfarin and phenytoin Increased efficacy of omeprazole, increased toxicity of mephenytoin Absence of codeine efficacy, no effect of encainide, increased levels of tricyclic antidepressants, fluoxetine, phenothiazines Sustained paralysis to succinylcholine, possible increased toxicity of cocaine Unknown... 

A2 Acetaminophen, antipyrine, caffeine, clomipramine, phenacetin, tacrine, tamoxifen, theophylline, warfarin Smoking, charcoal-broiled foods, cruciferous vegetables, omeprazole Galangin, furafylline, fluvoxamine... 

C19 TCAs, citalopram (partly), warfarin, tolbutamide, phenytoin, diazepam Fluoxetine, fluvoxamine, sertraline, imipramine, ketoconozole, omeprazole Rifampin... 

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... 

Alcohol should be avoided during furazolidone and metronidazole therapy. Toxic psychosis has been seen in patients under treatment with furazolidone. Metronidazole should be used with caution when coadministering with warfarin, phenytoin, lithium, omeprazole, and phenobarbital. The coadministration of pentamidine with drugs toxic to the kidney should be avoided. 

ANTICOAGULANTS-ORAL PROTON PUMP INHIBITORS Possibly t anticoagulant effect when esomeprazole, lansoprazole or omeprazole is added to warfarin Uncertain at present. Omeprazole and lansoprazole are known to induce CYP1A2, which plays a role in activation of coumarins Monitor INR more closely. 1 dose may be required. If 10%, 20% or 30% over range, omit dose for 1, 2 or 3 days respectively consider i maintenance dose by 10%. Regular dosing of a proton pump inhibitor is preferable if affects INR significantly. Not reported with pantoprazole or rabeprazole... 

Gastrointestinal drugs. Avoid cimetidine and omeprazole which inhibit the clearance of R warfarin, and sucralfate which may impair its absorption. Ranitidine may be used but INR should be checked if the dose is high. Most antacids are safe. 

Adverse effects include nausea, headache, diarrhoea, constipation and rash but are uncommon. Omeprazole inhibits the 2C family of the cytochrome P450 system, decreasing the metabolism of warfarin, diazepam, carbamazepine and phenytoin, and enhancing the action of these drugs (but inhibition is less than with cimetidine). 

E)rug5 that influence nutrient metabolism are discussed in various sections. These drugs include lovastatin, pravastatin, omeprazole, dilantin, methotrexate, allopurinol, warfarin, furosemide, thiouracil, and diphosphonatc. Alcohol is also discussed in this context because, depending on its intake, it functions as a food, drug, or toxin. 

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