Drug interactions
Clemastine + Clonazepam
Severity: Moderate
Clemastine and Clonazepam: 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 first-generation antihistamine, and combined use with clonazepam can increase drowsiness and reduce alertness. Elderly patients are more prone to confusion and falls.
What this interaction means in plain words
Clemastine and Clonazepam 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; Clonazepam belongs to Central Nervous System.
Why it happens
Additive CNS depression from central H1 blockade and GABA-A potentiation.
What to do
Consider a non-sedating antihistamine instead. If both are used, counsel on avoiding driving and alcohol.
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 Clonazepam
- Calcium / magnesium / potassium / sodium oxybates + Clonazepam Contraindicated
- Clonazepam + Sodium oxybate Contraindicated
- Alfentanil + Clonazepam Major
- Alprazolam + Clonazepam Major
- Amobarbital + Clonazepam Major
- Belladonna and opium + Clonazepam Major
Other interactions of Clemastine
Frequently asked questions
Can I take Clemastine with Clonazepam?
MediHelp rates the interaction as moderate. Clemastine and Clonazepam 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 first-generation antihistamine, and combined use with clonazepam can increase drowsiness and reduce alertness. Elderly patients are more prone to confusion and falls.
How serious is the interaction between Clemastine and Clonazepam?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Consider a non-sedating antihistamine instead. If both are used, counsel on avoiding driving and alcohol.
What other medicines interact with Clonazepam?
MediHelp also lists interactions of Clonazepam with, for example, Calcium / magnesium / potassium / sodium oxybates, Sodium oxybate, Alfentanil. The full list is on the Clonazepam page.
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