Cyclobenzaprine and Clozapine Interaction

Drug interaction information between Cyclobenzaprine and Clozapine.

Cyclobenzaprine and Clozapine have a documented moderate interaction in FDA labeling.

FDA drug labeling documents a moderate-severity interaction between Cyclobenzaprine and Clozapine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Cyclobenzaprine

Muscle Relaxant

Drug B

Clozapine

Atypical Antipsychotic

How They Interact

Both drugs have similar side effects that can slow down your digestive system and cause confusion or dry mouth. Combining them makes these side effects much more likely and can lead to severe constipation or toxicity.

FDA Label Information

Anticholinergic Drugs Concomitant treatment with clozapine and other drugs with anticholinergic activity (e.g., benztropine, cyclobenzaprine, diphenhydramine) can increase the risk for anticholinergic toxicity and severe gastrointestinal adverse reactions related to hypomotility.

Frequently Asked Questions

What SPL severity band is on file for Cyclobenzaprine + Clozapine?

Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Clozapine has 42 labeled pairs on file vs Cyclobenzaprine's 17. In the moderate band specifically: Cyclobenzaprine has 3 (also Tapentadol, Tranylcypromine); Clozapine has 3 (also Diphenhydramine, Fluoxetine).

What mechanism field is on file for Cyclobenzaprine and Clozapine?

Both drugs have similar side effects that can slow down your digestive system and cause confusion or dry mouth. Combining them makes these side effects much more likely and can lead to severe constipation or toxicity.

Clozapine's labeled portfolio outnumbers Cyclobenzaprine

SPL source-record counts only. This page's band is moderate · classes on file: Cyclobenzaprine (Muscle Relaxant); Clozapine (Atypical Antipsychotic).

Cyclobenzaprine

0 major · 3 moderate · 14 minor · 17 total

Clozapine

0 major · 3 moderate · 39 minor · 42 total

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.