Phentermine and Rasagiline interaction
Phentermine and Rasagiline: 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 Phentermine (Phentermine hydrochloride) label · effective 2026-08-17
…cardiovascular disease (e.g., coronary artery disease, stroke, arrhythmias, congestive heart failure, uncontrolled hypertension) • During or within 14 days following the administration of monoamine oxidase inhibitors • Hyperthyroidism • Glaucoma • Agitated states • History of drug abuse • Pregnancy [ see Use in Specific Populations () ] • Nursing [ see Use in Specific…
Monoamine Oxidase Inhibitors Use of phentermine is contraindicated during or within 14 days following the administration of monoamine oxidase inhibitors because of the risk of hypertensive crisis.
• Monoamine oxidase inhibitors: Risk of hypertensive crisis.
The safety and efficacy of combination therapy with phentermine and any other drug products for weight loss including prescribed drugs, over-the-counter preparations, and herbal products, or serotonergic agents such as selective serotonin reuptake inhibitors (e.g., fluoxetine, sertraline, fluvoxamine, paroxetine), have not been established.
From the Rasagiline label · effective 2020-06-30
Hypertensive crisis has been reported in patients taking the recommended dose of rasagiline and sympathomimetic medications.
Severe hypertension has been reported in patients taking the recommended dose of rasagiline and ophthalmic drops containing sympathomimetic medications.
Nevertheless, caution should be exercised when concomitantly using recommended doses of rasagiline with any sympathomimetic medications including nasal, oral, and ophthalmic decongestants and cold remedies.
Sympathomimetic Medications The concomitant use of rasagiline and sympathomimetic medications was not allowed in clinical studies.
Severe hypertensive reactions have followed the administration of sympathomimetics and nonselective MAO inhibitors.
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.