Drug interactions
Methamphetamine + Promazine
Severity: Moderate
Methamphetamine 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 with sedating, anticholinergic and alpha-blocking effects, and it can prolong the QT interval. Combined with methamphetamine, there may be additive effects on heart rhythm, and the stimulant and antipsychotic effects oppose each other, particularly in predisposed patients.
What this interaction means in plain words
Methamphetamine 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
Pharmacodynamic: the stimulant's sympathomimetic arrhythmogenic effects combine with the phenothiazine's QT prolongation and opposing dopaminergic activity.
What to do
Check ECG and electrolytes in patients with cardiac risk factors. Avoid use in patients with a history of QT prolongation or arrhythmia.
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?
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Other interactions of Methamphetamine
- Isocarboxazid + Methamphetamine Contraindicated
- Linezolid + Methamphetamine Contraindicated
- Methamphetamine + Phenelzine Contraindicated
- Methamphetamine + Procarbazine Contraindicated
- Methamphetamine + Rasagiline Contraindicated
- Methamphetamine + Safinamide Contraindicated
Frequently asked questions
Can I take Methamphetamine with Promazine?
MediHelp rates the interaction as moderate. Methamphetamine 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 with sedating, anticholinergic and alpha-blocking effects, and it can prolong the QT interval. Combined with methamphetamine, there may be additive effects on heart rhythm, and the stimulant and antipsychotic effects oppose each other, particularly in predisposed patients.
How serious is the interaction between Methamphetamine 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: Check ECG and electrolytes in patients with cardiac risk factors. Avoid use in patients with a history of QT prolongation or arrhythmia.
What other medicines interact with Methamphetamine?
MediHelp also lists interactions of Methamphetamine with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Methamphetamine page.
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