Phenytoin and Tretinoin interaction
Phenytoin and Tretinoin: the Tretinoin prescribing label flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Tretinoin label · effective 2026-05-26
Avoid concomitant use with strong CYP3A inducers if possible.
Strong CYP3A Inducers Concomitant use of tretinoin capsules with strong CYP3A4 inducers may decrease tretinoin plasma concentrations, which may reduce its efficacy.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.