Lansoprazole Warfarin

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. 

Deravirdine (Rescnptor) [Antiretroviral/NNRTI] Uses HIV Infxn Action Nonnucleoside RT inhibitor Dose 400 mg PO tid Caution [C, ] CDC recommends HIV-infected mothers not to breast-feed (transmission risk) w/ renal/hepatic impair Contra Use w/ drugs dependent on CYP3A for clearance (Table VI-8) Disp Tabs SE Fat redistribution, immune reconstitution synd, HA, fatigue, rash, T transaminases, N/V/D Interactions T Effects W/ fluoxetine T effects OF benzodiazepines, cisapride, clarithromycin, dapsone, ergotamine, indinavir, lovastatin, midazolam, nifedipine, quinidine, ritonavir, simvastatin, terfena-dine, triazolam, warfarin effects W/ antacids, barbiturates, carbamazepine, cimetidine, famotidine, lansoprazole, nizatidine, phenobarbital, phenytoin, ranitidine, rifabutin, rifampin effects OF didanosine EMS Use of benzodiazepines and CCBs should be avoided may cause a widespread rash located on upper body and arms OD May cause an extension of nl SEs symptomatic and supportive Deferasirox (Exjade) [Iron Chelator] Uses Chronic iron overload d/t transfusion in pts >2 y Action Oral iron chelator Dose Initial 20 mg/kg... 

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... 

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... 

In pharmacological studies, omeprazole caused a minor increase in k-warfarin levels, with no or a minor increase in anticoagulant effect. Conversely, lansoprazole, pantoprazole and rabeprazole did not alter warfarin pharmacokinetics or anticoagulant effect Omeprazole does not appear to alter the effects of aeenoeoumarol and pantoprazole does not appear to later the effects of phenpro-coumon. Nevertheless, a number of isolated reports describe increased anticoagulant effects when PPIs are given with coumarins. 

A study in 24 healthy subjects stabilised on warfarin found that lansoprazole 60 mg daily for 9 days had no effect on the pharmacokinetics of either S- orR-warfarin, and did not alter the effect of warfarin on prothrombin times. ... 

However, in 1998 the manufacturers of lansoprazole had on record two reports of possible interactions. An elderly patient taking warfarin developed an INR of 7 when lansoprazole was added. Despite a warfarin dosage adjustment he had a gastrointestinal haemorrhage, a myocardial infarction and died after 3 weeks. Another man taking warfarin (as well as amiodarone, furosemide and lisinopril) became confused, had hallucinations and developed an increased INR (value not known) when given lansoprazole. The lansoprazole was stopped after 4 days, and he then recovered. However, it is uncertain whether this was an interaction or whether he had taken an incorrect warfarin dosage because of his confusion. ... 

Cavanaugh JH, Winters EP, Cohen A, Locke CS, Braeckman R. Lack of effect of lansoprazole on steady state warfarin metabolism. Gastroenterology (1991) 100, A40. 

Imatinib increases serum tacrolimus levels and is therefore predicted to increase ciclosporin levels. Imatinib may also increases the levels of some benzodiazepines (e.g. midazolam), some calcium-channel blockers (e.g. nifedipine), oestrogens, paracetamol, pimozide, and warfarin. In one case lansoprazole was suspected to have raised imatinib levels. 

Class 2 (High PermeabiUty, Low Solrrbility) Azathioprine, Azithromycin, Alprazolam, Warfarin, Haloperidol, Glipizide, Griseofulvinum, Danazol, Dapsone, Diclofenac, Indometacin, Itraconzol, Carbamazepine, Carvedilol, Ketoconazole, Lansoprazol, Mebendazole, Mefloqrrine, Nalidixic acid. Nevirapine, Piroxicam, Praziquantel, Ritonavir, Rifampicinirm, Spironolactone, Tamoxifen, Terfenadine, Trimethoprim, Ibnprofen, lopanoic add, Lovastatin, Naproxen, Oxaprozin, Flubiprofen, Cisapride. ... 

Information on possible drug interactions with lansoprazole is incomplete [59]. Some pertinent drugs have been studied only at standard dosage (prednisone [60]), not at all (carbamazepine), or data were published only in descriptive terms (warfarin [61]). However, compounds representative of most CYP isoforms have been studied with negative results [20, 60], with the notable exception of 2D6 (not investigated). 

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