Drug interactions
Meperidine + Phendimetrazine
Severity: Moderate
Meperidine and Phendimetrazine: 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
Phendimetrazine is a sympathomimetic anorectic whose stimulant effect may partly offset opioid sedation but does not prevent respiratory depression. Meperidine can also have serotonergic activity, and combining it with stimulants and sympathomimetics might raise the risk of agitation, tachycardia and hypertension.
What this interaction means in plain words
Meperidine and Phendimetrazine 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
Opposing CNS effects with possible additive sympathomimetic and serotonergic activity; the clinical effect is not well defined.
What to do
Monitor blood pressure, heart rate and mental status after starting the combination. Do not rely on the stimulant to counteract opioid sedation.
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 Meperidine
- Alvimopan + Meperidine Contraindicated
- Isocarboxazid + Meperidine Contraindicated
- Meperidine + Methylene blue Contraindicated
- Meperidine + Olanzapine / samidorphan Contraindicated
- Meperidine + Phenelzine Contraindicated
- Meperidine + Procarbazine Contraindicated
Frequently asked questions
Can I take Meperidine with Phendimetrazine?
MediHelp rates the interaction as moderate. Meperidine and Phendimetrazine 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. Phendimetrazine is a sympathomimetic anorectic whose stimulant effect may partly offset opioid sedation but does not prevent respiratory depression. Meperidine can also have serotonergic activity, and combining it with stimulants and sympathomimetics might raise the risk of agitation, tachycardia and hypertension.
How serious is the interaction between Meperidine and Phendimetrazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure, heart rate and mental status after starting the combination. Do not rely on the stimulant to counteract opioid sedation.
What other medicines interact with Meperidine?
MediHelp also lists interactions of Meperidine with, for example, Alvimopan, Isocarboxazid, Methylene blue. The full list is on the Meperidine page.
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