Omeprazole Paracetamol

CYP1A2 caffeine, imipramine, paracetamol, theophylline cigarette smoke, omeprazole cimetidine, ciprofloxacin, enoxacin, fluvoxamine... 

Omeprazole 20 mg daily for 8 days had no effect on the pharmacokinetics of phenacetin, or paracetamol derived from phenacetin, in 10 healthy subjects, except that the peak plasma level of phenacetin was higher. There was no change in the metabolism (oxidative and conjugative) of phenacetin or derived paracetamol. In another study, omeprazole 40 mg daily for 7 days had no effect on the formation of thioether metabolites of paracetamol in 5 rapid and 5 slow metabolisers of 5-mephenytoin [a probe drug for CYP2C19 activity, see Genetic factors in drug metabolism , (p.4)].3... 

The findings from these studies suggest that neither lansoprazole nor omeprazole cause any clinically important changes in the pharmacokinetics of paracetamol. No special precautions appear to be needed on concurrent... 

The UK manufacturers report that in interaction clinical studies there was no evidence of clinically relevant interactions between letrozole and other commonly prescribed drugs, namely benzodiazepines such as diazepam, barbiturates, diclofenac, fiirosemide, ibuprofen, omeprazole, and paracetamol (acetaminophen). ... 

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