Cyclobenzaprine and Lithium interaction

Cyclobenzaprine and Lithium: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.

Major

Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.

What the FDA labels say

From the Cyclobenzaprine (TONMYA) label · effective 2026-08-14

Major

If serotonin syndrome symptoms occur with the use of other serotonergic drugs, immediately discontinue TONMYA.

Drug interactionsby drug classView label on DailyMed
Major

Other serotonergic Drugs: Serotonin syndrome has been reported ( 5.2 , 7 )

Drug interactionsby drug classView label on DailyMed
Moderate

If concomitant treatment with TONMYA and other serotonergic drugs is clinically warranted, careful observation is advised, particularly during treatment initiation or dosage increases.

Warnings and precautionsby drug classView label on DailyMed
Moderate

If concomitant treatment with TONMYA and other serotonergic drugs (besides MAO inhibitors) is clinically warranted, careful observation is advised, particularly during dosage increases.

Drug interactionsby drug classView label on DailyMed

From the Lithium (Lithium Carbonate) label · effective 2026-06-04

Major

If concomitant use of lithium with other serotonergic drugs is clinically warranted, inform patients of the increased risk for serotonin syndrome and monitor for symptoms.

Warnings and precautionsby drug classView label on DailyMed
Moderate

The risk is increased with concomitant use of other serotonergic drugs (including selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, triptans, tricyclic antidepressants, fentanyl, tramadol, tryptophan, buspirone, and St.

Warnings and precautionsby drug classView label on DailyMed

Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.

Open in the checker

Not medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.