Drug interactions
Dexfenfluramine + Isoniazid
Severity: Moderate
Dexfenfluramine and Isoniazid: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Dexfenfluramine releases serotonin and blocks its reuptake, and isoniazid has weak MAO inhibiting activity. Combined use could increase risk of serotonin syndrome. Dexfenfluramine is withdrawn in most markets.
What this interaction means in plain words
Dexfenfluramine and Isoniazid can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Serotonin release and reuptake inhibition combined with weak MAO inhibition.
What to do
Avoid the combination if possible. Monitor for agitation, tremor, hyperthermia, and autonomic instability.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Dexfenfluramine and Isoniazid, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Isoniazid
Frequently asked questions
Can I take Dexfenfluramine with Isoniazid?
MediHelp rates the interaction as moderate. Dexfenfluramine and Isoniazid can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Dexfenfluramine releases serotonin and blocks its reuptake, and isoniazid has weak MAO inhibiting activity. Combined use could increase risk of serotonin syndrome. Dexfenfluramine is withdrawn in most markets.
How serious is the interaction between Dexfenfluramine and Isoniazid?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination if possible. Monitor for agitation, tremor, hyperthermia, and autonomic instability.
What other medicines interact with Isoniazid?
MediHelp also lists interactions of Isoniazid with, for example, Bacillus calmette-guerin substrain tice, Benzhydrocodone / acetaminophen, Carbamazepine. The full list is on the Isoniazid page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
