Pantoprazole Warfarin

Pantoprazole (Protonix) [Gastric Acid Suppressant/Proton Pump Inhibitor] Uses GERD, erosive gastritis, ZE synd, PUD Action Proton pump inhibitor Dose 40 mg/d PO do not crush/chew tabs 40 mg IV/d (not >3 mg/min, use Protonix filter) Caution [B, /-] Disp Tabs, inj SE Chest pain, anxiety, GI upset Interactions t Effects OF warfarin t effects of photosensitivity W/ St. John s wort X effects OF ketoconazole EMS t Effects of anticoagulants may affect glucose (hypoglycemia) OD Unlikely to cause life-threatening Sxs... 

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... 

Several agents commonly used in the CKD population have been evaluated for interactions with cinacalcet. Coadministration of calcium carbonate or sevelamer did not affect the pharmacokinetics of cinacalcet. Pantoprazole did not alter the pharmacokinetics of cinacalcet HCl, an important finding since pantoprazole alters gastric pH, and the solubility of cinacalcet decreases as the gastric pH rises over 5.5. Coadministration of cinacalcet with warfarin also did not affect the pharmacokinetics of warfarin. Coadministration of cinacalcet and ketoconazole, a strong inhibitor of CYP3A4, resulted in an increase in the area under the curve and maximum concentration of 2.3 and 2.2 times, respectively. Concurrent administration of cinacalcet with amitriptyline increased amitriptyline exposure and nortriptyhne (active metabohte) exposure by approximately 20% in CYP2D6-extensive metabohzers. 

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. 

In 26 healthy subjects, pantoprazole 40 mg daily for 8 days caused no change in the response to a single 25-mg dose of warfarin given on day 2. The pharmacokineties of R- and 5-warfarin were unaltered, and no changes in the pharmaeodynamies of the warfarin (prothrombin time, factor Vff) were seen." However, the manufaeturer notes that there have been reports of inereased INR and prothrombin time in patients taking pantoprazole and warfarin. ... 

Duursema L, Muller FO, Schall R, Middle MV, Hundt HKL, Groenewoud G, Steinijans VW, BHesatii H. Lack of effect of pantoprazole on the pharmacodynamics and phannacckinetics of warfarin BrJ Clin Pharmacol (1995) 39,700-703. 

A 69-year-old woman developed confusion and paranoia over several days. She was taking carvedilol 12 mg bd, warfarin 2 mg/day, folic add 1 mg/day, levothyroxine 100 micro-grams/day, pantoprazole 40 mg/day, paroxetine 40 mg/day, and flecainide 100 mg bd. The flecainide had been started 2 weeks before. The plasma flecainide concentration was 1.36 mg/1. Paroxetine was withdrawn and the dosage of flecainide was reduced to 50 mg bd. Her delirium resolved 3 days later. 

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