Prazole Plus Drug Interactions

Pantoprazole: Pantoprazole is metabolized through the CYP450 system, primarily the CYP2C19 and CYP3A4 isoenzymes, and subsequently undergoes phase II conjugation. Based on studies evaluating possible interactions of pantoprazole with other drugs metabolized by the CYP450 system, no dosage adjustment is needed with concomitant use of the following drugs: Theophylline, cisapride, antipyrine, caffeine, carbamazepine, diazepam, diclofenac, digoxin, ethanol, glyburide, oral contraceptives (levonorgestrel, ethynylestradiol), metoprolol, nifedipine, phenytoin or warfarin. Clinically relevant interactions of pantoprazole with other drugs with the same metabolic pathways are not expected. Therefore, when co-administered with pantoprazole, adjustment of the dosage of pantoprazole with such drugs may not be necessary. There was also no interaction with concomitantly administered antacids. Because of profound and long lasting inhibition of gastric acid secretion, it is theoretically possible that pantoprazole may interfere with absorption of drugs where gastric pH is an important determinant of their bioavailability (eg, ketoconazole, ampicillin esters and iron salts).
Domperidone: Anticholinergic drugs may inhibit the antidyspeptic effects of domperidone. Antimuscarinic agents and opioid analgesics may antagonize the effect of domperidone. Domperidone suppresses the peripheral effects (digestive disorders, nausea and vomiting) of dopaminergic agonists. Since domperidone has gastrokinetic effects, it could influence the absorption of concomitant orally administered drugs, particularly those with sustained-release or enteric-coated formulations. As domperidone interferes with serum prolactin levels, it may interfere with other hypoprolactinemic agents and with some diagnostic tests. Antacids and antisecretory agents lower the oral bioavailability of domperidone. They should be taken after meals and not before meals ie, they should not be taken simultaneously with domperidone. Reduced gastric acidity impairs the absorption of domperidone. Oral bioavailability is decreased by prior administration of cimetidine or sodium carbonate.