Drug interactions
Chlorpheniramine + Chlorzoxazone
Severity: Moderate
Chlorpheniramine and Chlorzoxazone: 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
Chlorpheniramine is a sedating first-generation antihistamine that can increase the drowsiness caused by chlorzoxazone. Alertness and coordination may be reduced.
What this interaction means in plain words
Chlorpheniramine and Chlorzoxazone 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.
Chlorpheniramine belongs to Respiratory; Chlorzoxazone belongs to Musculoskeletal.
Why it happens
Additive CNS depression.
What to do
Warn about drowsiness and avoid driving until the effect is known. Consider a non-sedating antihistamine as an alternative.
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 Chlorzoxazone
Other interactions of Chlorpheniramine
Frequently asked questions
Can I take Chlorpheniramine with Chlorzoxazone?
MediHelp rates the interaction as moderate. Chlorpheniramine and Chlorzoxazone 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. Chlorpheniramine is a sedating first-generation antihistamine that can increase the drowsiness caused by chlorzoxazone. Alertness and coordination may be reduced.
How serious is the interaction between Chlorpheniramine and Chlorzoxazone?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Warn about drowsiness and avoid driving until the effect is known. Consider a non-sedating antihistamine as an alternative.
What other medicines interact with Chlorzoxazone?
MediHelp also lists interactions of Chlorzoxazone with, for example, Alfentanil, Alprazolam, Amobarbital. The full list is on the Chlorzoxazone page.
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