Drug interactions
Dantrolene + Diphenhydramine
Severity: Moderate
Dantrolene and Diphenhydramine: 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
Diphenhydramine is a first-generation antihistamine with strong sedative effects, and dantrolene commonly causes drowsiness. The pair may produce greater sedation and psychomotor impairment, especially in older adults.
What this interaction means in plain words
Dantrolene and Diphenhydramine 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.
Dantrolene belongs to Musculoskeletal; Diphenhydramine belongs to Respiratory.
Why it happens
Additive central nervous system depression.
What to do
Monitor for oversedation and falls, and avoid or limit diphenhydramine in elderly patients. Consider a non-sedating antihistamine where an antihistamine is needed.
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 Dantrolene
Other interactions of Diphenhydramine
Frequently asked questions
Can I take Dantrolene with Diphenhydramine?
MediHelp rates the interaction as moderate. Dantrolene and Diphenhydramine 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. Diphenhydramine is a first-generation antihistamine with strong sedative effects, and dantrolene commonly causes drowsiness. The pair may produce greater sedation and psychomotor impairment, especially in older adults.
How serious is the interaction between Dantrolene and Diphenhydramine?
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 for oversedation and falls, and avoid or limit diphenhydramine in elderly patients. Consider a non-sedating antihistamine where an antihistamine is needed.
What other medicines interact with Dantrolene?
MediHelp also lists interactions of Dantrolene with, for example, Benzhydrocodone / acetaminophen, Buprenorphine long-acting, Buprenorphine subdermal implant. The full list is on the Dantrolene page.
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