Pantoprazole Phenytoin

PHENYTOIN PROTON PUMP INHIBITORS Possible t efficacy and adverse effects of phenytoin Unclear possible altered metabolism via CYP2C19 1 dose may be required. Use the proton pump inhibitor regularly, not PRN monitor phenytoin levels when starting or stopping treatment. Patients have received omeprazole for 3 weeks without altered phenytoin levels. Effect not reported with pantoprazole or rabeprazole... 

Allergic interstitial nephritis Penicillins, rifampin, sulfonamides, thiazides, cimetidine.phenytoin, allopurinol, furosemide, NSAIDS, ciprofloxacin, pantoprazole, omeprazole, atazanavir, bevacizumab Rash, fever, eosinophilia, eosinophiluria, pyuria... 

Proton pnmp inhibitors Omeprazole Lansoprazole Pantoprazole Antiepileptics Diazepam Phenytoin Phenobarbitone Amitriptyline Clomipramine Cyclophosphamide Progesterone... 

A study in epileptic patients found that omeprazole 20 mg daily did not affect the serum levels of phenytoin, whereas earlier studies in healthy subjects su ested that phenytoin levels might be modestly raised by omeprazole 40 mg daily. A study with esome-prazole also suggests it may cause a minor rise in phenytoin levels. Lansoprazole does not normally affect phenytoin levels, but an isolated case report of toxicity is tentatively attributed to an interaction. Pantoprazole and rabeprazole appear not to interact. 

In a randomised, crossover study in 23 healthy subjects it was found that pantoprazole 40 mg daily for 7 days did not alter the pharmacokinetics (AUC, maximum serum levels, half-life) of a single 300-mg dose of phenytoin. This study has also been published elsewhere. ... 

Information is very limited but it seems that omeprazole 20 mg daily does not affect serum phenytoin levels, whereas 40 mg daily may possibly cause a slight increase. No special precautions would normally seem necessary if lansoprazole or omeprazole is given with phenytoin, but until more is known it would be prudent to be aware of this possible interaction if concurrent use is necessary. Similarly, the manufacturers of esomepra-zole suggest concurrent use should be monitored, although the elevation in levels seen in the study would not usually be expected to be clinically significant. More study is needed. No special precautions would seem to be necessary if rabeprazole or pantoprazole and phenytoin are given concurrently. 

Middle MV, Muller FO, Schall R, Groenewoud G, Hundt HKL, Huber R, Bliesath H, Stein-ijans VW. No influence of pantoprazole on the pharmacokinetics of phenytoin. Int J Clin Pharmacol Ther 995) 33, 304-7. 

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