Benzphetamine and Phentermine interaction
Benzphetamine and Phentermine: both prescribing labels 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 Benzphetamine (Benzphetamine Hydrochloride) label · effective 2026-06-18
Benzphetamine Hydrochloride Tablets should not be used concomitantly with other CNS stimulants.
Benzphetamine hydrochloride tablets should not be used concomitantly with other CNS stimulants.
From the Phentermine (Phentermine hydrochloride) label · effective 2026-08-17
Risk of Abuse and Dependence Phentermine is related chemically and pharmacologically to amphetamine (d- and d l l-amphetamine) and other related stimulant drugs that have been extensively abused.
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.