Drug interactions
Clemastine + Phenelzine
Severity: Moderate
Clemastine and Phenelzine: 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
Clemastine is a sedating antihistamine with anticholinergic activity, and phenelzine can add to its CNS depressant and anticholinergic effects. Drowsiness, confusion and urinary retention may be more pronounced.
What this interaction means in plain words
Clemastine and Phenelzine 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.
Clemastine belongs to Respiratory; Phenelzine belongs to Central Nervous System.
Why it happens
Additive CNS depression and anticholinergic effects, with MAO inhibition potentially prolonging antihistamine anticholinergic activity.
What to do
Prefer a non-sedating antihistamine, or use the lowest dose and monitor for oversedation and anticholinergic effects, especially in older patients.
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 Phenelzine
- 5-HTP + Phenelzine Contraindicated
- Amitriptyline + Phenelzine Contraindicated
- Amoxapine + Phenelzine Contraindicated
- Atomoxetine + Phenelzine Contraindicated
- Benzphetamine + Phenelzine Contraindicated
- Brimonidine + Phenelzine Contraindicated
Other interactions of Clemastine
Frequently asked questions
Can I take Clemastine with Phenelzine?
MediHelp rates the interaction as moderate. Clemastine and Phenelzine 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. Clemastine is a sedating antihistamine with anticholinergic activity, and phenelzine can add to its CNS depressant and anticholinergic effects. Drowsiness, confusion and urinary retention may be more pronounced.
How serious is the interaction between Clemastine and Phenelzine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Prefer a non-sedating antihistamine, or use the lowest dose and monitor for oversedation and anticholinergic effects, especially in older patients.
What other medicines interact with Phenelzine?
MediHelp also lists interactions of Phenelzine with, for example, 5-HTP, Amitriptyline, Amoxapine. The full list is on the Phenelzine page.
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