Cyclobenzaprine and Quetiapine interaction
Cyclobenzaprine and Quetiapine: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
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
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…
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) ].
CNS Depressants: CNS depressant effects of alcohol, barbiturates, and other CNS depressants may be enhanced ( 5.5 , 7 )
From the Quetiapine (SEROQUEL XR) label · effective 2026-04-10
• Anticholinergic (antimuscarinic) Effects: Use with caution with other anticholinergic drugs and in patients with urinary retention, prostatic hypertrophy, or constipation (5.20)
Other important considerations in the differential diagnosis include central anticholinergic toxicity, heat stroke, drug fever, and primary central nervous system (CNS) pathology.
This contributes to anticholinergic adverse reactions when SEROQUEL XR is used at therapeutic doses, taken concomitantly with other anticholinergic medications, or taken in overdose.
SEROQUEL XR should be used with caution in patients receiving medications having anticholinergic (antimuscarinic) effects [see Drug Interactions (7.1) , Overdosage (10.1) , and Clinical Pharmacology (12.1) ] .
Anticholinergic Drugs: Concomitant treatment with quetiapine and other drugs with anticholinergic activity can increase the risk for severe gastrointestinal adverse reactions related to hypomotility.
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Open in the checkerNot 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.