Chlorpromazine and Cyclobenzaprine interaction

Chlorpromazine and Cyclobenzaprine: 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 Chlorpromazine (Chlorpromazine Hydrochloride) label · effective 2026-02-02

Major

Do not use in comatose states or in the presence of large amounts of central nervous system depressants (alcohol, barbiturates, narcotics, etc.).

Contraindicationsby drug classView label on DailyMed
Moderate

Because of its CNS depressant effect, chlorpromazine should be used with caution in patients with chronic respiratory disorders such as severe asthma, emphysema and acute respiratory infections, particularly in children (1 to 12 years of age).

Precautionsby drug classView label on DailyMed
Moderate

Chlorpromazine prolongs and intensifies the action of CNS depressants such as anesthetics, barbiturates and narcotics.

Precautionsby drug classView label on DailyMed
Moderate

When chlorpromazine is not being administered to reduce requirements of CNS depressants, it is best to stop such depressants before starting chlorpromazine treatment.

Precautionsby drug classView label on DailyMed

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

Major

Based on its structural similarity to TCAs, concomitant use of TONMYA with: MAO inhibitors may be life-threatening [see Contraindications (4) ] , Alcohol, barbiturates, and other CNS depressants may increase the risk of adverse reactions associated with these drugs, Tramadol may increase the seizure risk, Guanethidine or other similar acting drugs may block the…

Drug interactionsby drug classView label on DailyMed
Moderate

CNS Depression and Risk of Operating a Motor Vehicle or Hazardous Machinery TONMYA monotherapy may cause CNS depression and concomitant use of TONMYA with alcohol, barbiturates, or other CNS depressants may increase the risk of CNS depression [see Drug Interactions (7) ].

Warnings and precautionsby drug classView label on DailyMed
Moderate

CNS Depressants: CNS depressant effects of alcohol, barbiturates, and other CNS depressants may be enhanced ( 5.5 , 7 )

Drug interactionsby drug classView label on DailyMed

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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.