Cyclobenzaprine and Lorazepam interaction

Cyclobenzaprine and Lorazepam: 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

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

From the Lorazepam (LOREEV XR) label · effective 2025-10-08

Major

Caution patients receiving LOREEV XR against operating machinery or driving a motor vehicle as well to avoid the concomitant use of alcohol and other CNS depressant drugs during treatment ( 5.4 , 7 )

Warnings and precautionsby drug classView label on DailyMed
Major

Prescribe the lowest effective dosage; avoid or minimize concomitant use of CNS depressants and other substances associated with abuse, misuse, and addiction (e.g., opioid analgesics, stimulants); and advise patients on the proper disposal of unused drug.

Warnings and precautionsby drug classView label on DailyMed
Major

Use of benzodiazepines, including LOREEV XR, both used alone and in combination with other CNS depressants, may lead to potentially fatal respiratory depression.

Warnings and precautionsby drug classView label on DailyMed
Major

Alcohol should be avoided and other CNS depressant drugs used with caution during treatment with LOREEV XR [see Drug Interactions ( 7 )] .

Warnings and precautionsby drug classView label on DailyMed
Moderate

CNS depressants: Additive CNS depressant effects (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.