Theophylline with proton pump inhibitors

CIMETIDINE FAMOTIDINE NIZATIDINE, RANITIDINE BRONCHODILATORS -THEOPHYLLINE t efficacy and adverse effects, including seizures. There is conflicting information associated with ranitidine, famotidine and nizatidine Inhibition of metabolism via CYP1A2, cimetidine being the best known inhibitor Use alternative acid suppression, e.g. a proton pump inhibitor (not omeprazole or lansoprazole) or monitor closely considerable patient variation. Check levels on day 3 and then at 1 week. A 30-50% i dose of theophylline may be required. For doses <400 mg/day, the interaction may not be clinically significant... 

Lansoprazole possibly induces cytochrome P450 isoenzyme CYP1A2 (the enzyme by which theophylline is metabolised) to a small extent, but this is unlikely to be significant unless an individual is particularly sensitive to this effect. Other proton pump inhibitors are unlikely to interact with theophylline, and so no special precautions would seem necessary on eoneurrent use. 

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