Drug interactions
Cyclobenzaprine + Primidone
Severity: Moderate
Cyclobenzaprine and Primidone: 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
Primidone, partly metabolized to phenobarbital, causes sedation and when combined with cyclobenzaprine may produce excessive drowsiness and impaired coordination. Enzyme induction by the phenobarbital metabolite may also reduce cyclobenzaprine levels.
What this interaction means in plain words
Cyclobenzaprine and Primidone 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.
Cyclobenzaprine belongs to Musculoskeletal; Primidone belongs to Central Nervous System.
Why it happens
Additive CNS depression plus hepatic enzyme induction.
What to do
Monitor for sedation and falls, particularly after dose changes, and counsel against alcohol and driving.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Cyclobenzaprine and Primidone, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Cyclobenzaprine
- Cyclobenzaprine + Isocarboxazid Contraindicated
- Cyclobenzaprine + Linezolid Contraindicated
- Cyclobenzaprine + Phenelzine Contraindicated
- Cyclobenzaprine + Safinamide Contraindicated
- Cyclobenzaprine + Selegiline Contraindicated
- Cyclobenzaprine + Selegiline transdermal Contraindicated
Other interactions of Primidone
- Lorlatinib + Primidone Contraindicated
- Lurasidone + Primidone Contraindicated
- Primidone + Ranolazine Contraindicated
- Primidone + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
- Primidone + Voriconazole Contraindicated
- Abiraterone + Primidone Major
Frequently asked questions
Can I take Cyclobenzaprine with Primidone?
MediHelp rates the interaction as moderate. Cyclobenzaprine and Primidone 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. Primidone, partly metabolized to phenobarbital, causes sedation and when combined with cyclobenzaprine may produce excessive drowsiness and impaired coordination. Enzyme induction by the phenobarbital metabolite may also reduce cyclobenzaprine levels.
How serious is the interaction between Cyclobenzaprine and Primidone?
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 sedation and falls, particularly after dose changes, and counsel against alcohol and driving.
What other medicines interact with Cyclobenzaprine?
MediHelp also lists interactions of Cyclobenzaprine with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Cyclobenzaprine page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
