Lisdexamfetamine and Phentermine interaction
Lisdexamfetamine and Phentermine: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Lisdexamfetamine (Lisdexamfetamine Dimesylate) label · effective 2026-05-22
Additionally, in studies of another stimulant, there was slowing of the increase in height [see Adverse Reactions (6.1) ] .
Tricyclic Antidepressants Clinical Impact May enhance the activity of tricyclic or sympathomimetic agents causing striking and sustained increases in the concentration of d-amphetamine in the brain; cardiovascular effects can be potentiated.
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.