HERBAL MEDICINES OR DIETARY SUPPLEMENTS AND PHENOBARBITAL
St John's wort (Hypericum perforatum) is predicted to reduce the blood levels of phenobarbital.
The CSM in the UK advise that St John's wort should be stopped and that the phenobarbital dosage should be adjusted. However, note that this prediction also covered carbamazepine, which has subsequently been found not to interact, so a clinically significant interaction with phenobarbital now seems less likely.
The CSM in the UK advise that St John's wort should be stopped and that the phenobarbital dosage should be adjusted. However, note that this prediction also covered carbamazepine, which has subsequently been found not to interact, so a clinically significant interaction with phenobarbital now seems less likely.