Drug interactions
Dextroamphetamine + Promazine
Severity: Moderate
Dextroamphetamine and Promazine: 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
Promazine is a phenothiazine antipsychotic that can prolong the QT interval, and amphetamines may add arrhythmic risk through sympathetic stimulation. The antipsychotic also antagonizes dopaminergic stimulant effects, reducing the benefit of the amphetamine.
What this interaction means in plain words
Dextroamphetamine and Promazine 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
Additive cardiac effects (QT prolongation plus sympathomimetic stimulation) and pharmacodynamic dopamine antagonism.
What to do
Obtain a baseline ECG and monitor it in patients with cardiac risk factors or electrolyte disturbances. Reassess the need for both agents if palpitations or QT prolongation occur.
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 Dextroamphetamine and Promazine, 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 Dextroamphetamine
- Dextroamphetamine + Isocarboxazid Contraindicated
- Dextroamphetamine + Linezolid Contraindicated
- Dextroamphetamine + Methylene blue Contraindicated
- Dextroamphetamine + Phenelzine Contraindicated
- Dextroamphetamine + Rasagiline Contraindicated
- Dextroamphetamine + Safinamide Contraindicated
Frequently asked questions
Can I take Dextroamphetamine with Promazine?
MediHelp rates the interaction as moderate. Dextroamphetamine and Promazine 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. Promazine is a phenothiazine antipsychotic that can prolong the QT interval, and amphetamines may add arrhythmic risk through sympathetic stimulation. The antipsychotic also antagonizes dopaminergic stimulant effects, reducing the benefit of the amphetamine.
How serious is the interaction between Dextroamphetamine and Promazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Obtain a baseline ECG and monitor it in patients with cardiac risk factors or electrolyte disturbances. Reassess the need for both agents if palpitations or QT prolongation occur.
What other medicines interact with Dextroamphetamine?
MediHelp also lists interactions of Dextroamphetamine with, for example, Isocarboxazid, Linezolid, Methylene blue. The full list is on the Dextroamphetamine 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.
