Bupropion and Phentermine interaction
Bupropion and Phentermine: the Bupropion prescribing label 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 Bupropion (BUPROPION HCl ER (XL)) label · effective 2026-02-04
…medications that lower the seizure threshold (e.g., other bupropion products, antipsychotics, tricyclic antidepressants, theophylline, and systemic corticosteroids), metabolic disorders (e.g., hypoglycemia, hyponatremia, severe hepatic impairment, and hypoxia), or use of illicit drugs (e.g., cocaine) or abuse or misuse of prescription drugs such as CNS stimulants.
Drug-Laboratory Test Interactions: Bupropion hydrochloride extended-release tablets (XL) can cause false-positive urine test results for amphetamines (7.7).
Drug-Laboratory Test Interactions False-positive urine immunoassay screening tests for amphetamines have been reported in patients taking bupropion.
Confirmatory tests such as gas chromatography/mass spectrometry, will distinguish bupropion from amphetamines.
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.