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Cyclobenzaprine Disease Interactions

There are 2 disease interactions with cyclobenzaprine:


Cyclobenzaprine (Includes Cyclobenzaprine) ↔ Cardiovascular Disease

Severe Potential Hazard, Moderate plausibility

Applies to: Hyperthyroidism, Cardiovascular Disease, Cerebrovascular Insufficiency, History - Cerebrovascular Disease, History - Myocardial Infarction, Hypotension, Dehydration, Congestive Heart Failure

The manufacturers consider the use of cyclobenzaprine to be contraindicated in the acute recovery phase following myocardial infarction and in patients with hyperthyroidism, congestive heart failure, arrhythmias, heart block, and/or conduction disturbances. Cyclobenzaprine is structurally related to the tricyclic antidepressants, which have been reported to cause tachycardia, arrhythmias, heart block, hypertension, hypotension (particularly orthostatic hypotension), thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with cyclobenzaprine should be administered cautiously in patients with a history of cardiovascular or cerebrovascular disease or a predisposition to hypotension, particularly if the intended dosage exceeds those normally used for musculoskeletal conditions. Tachycardia, arrhythmia, palpitation, and hypotension have been reported with the use of cyclobenzaprine in less than 1% of patients.


  1. O'Riordan W, Gillette P, Calderon J, Stennes RL "Overdose of cyclobenzaprine, the tricyclic muscle relaxant." Ann Emerg Med 15 (1986): 592-3
  2. Linden CH, Mitchiner JC, Lindzon RD, Rumack BH "Cyclobenzaprine overdosage." J Toxicol Clin Toxicol 20 (1983): 281-8
  3. "Product Information. Flexeril (cyclobenzaprine)." Merck & Co, Inc, West Point, PA.

Cyclobenzaprine (Includes Cyclobenzaprine) ↔ Anticholinergic Effects

Moderate Potential Hazard, Moderate plausibility

Applies to: Gastrointestinal Obstruction, Glaucoma/Intraocular Hypertension, Urinary Retention

Cyclobenzaprine has anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with cyclobenzaprine should be administered cautiously in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. Glaucoma should be treated and under control prior to initiation of cyclobenzaprine therapy, and intraocular pressure monitored during therapy.


  1. Heckerling PS, Bartow TJ "Paradoxical diaphoresis in cyclobenzaprine poisoning." Ann Intern Med 101 (1984): 881
  2. "Product Information. Flexeril (cyclobenzaprine)." Merck & Co, Inc, West Point, PA.
  3. Linden CH, Mitchiner JC, Lindzon RD, Rumack BH "Cyclobenzaprine overdosage." J Toxicol Clin Toxicol 20 (1983): 281-8

cyclobenzaprine drug Interactions

There are 748 drug interactions with cyclobenzaprine

cyclobenzaprine alcohol/food Interactions

There is 1 alcohol/food interaction with cyclobenzaprine

Drug Interaction Classification

The classifications below are a general guideline only. It is difficult to determine the relevance of a particular drug interaction to any individual given the large number of variables.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No information available.

Do not stop taking any medications without consulting your healthcare provider.

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