Other hepatic enzyme inducers

Research summary

Hepatic enzyme induction is one of the best‑characterized mechanisms of pharmacokinetic interaction in humans. Controlled clinical studies show that potent inducers like rifampin, carbamazepine, phenytoin, and St. John’s Wort can decrease exposure to co‑administered drugs by 50–90% or more, principally through induction of CYP3A4, CYP2C9, CYP2C19, and certain UGT isoforms. In healthy volunteers, these effects are routinely demonstrated using probe drugs such as midazolam, oral contraceptive steroids, and other standardized substrates. There is no unified dietary supplement sold under the label “Other hepatic enzyme inducers”; instead, the term is used in drug–interaction tables to group miscellaneous agents that increase hepatic enzyme activity. Because most characterized inducers are prescription medications or herbal products used for specific conditions rather than for general health optimization, there is no evidence base to support using hepatic enzyme inducers as a beneficial “supplement” in healthy individuals. Research focuses almost entirely on their potential to reduce the effectiveness of other drugs or alter safety profiles, rather than on intrinsic health benefits.