cyclobenzaprine, Flexeril, Amrix, Fexmid

  • Pharmacy Author:
    Omudhome Ogbru, PharmD

    Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

  • Medical and Pharmacy Editor: Jay W. Marks, MD
    Jay W. Marks, MD

    Jay W. Marks, MD

    Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

Surprising Reasons You're in Pain Slideshow

PREPARATIONS: Tablets: 5 and 10 mg. Capsules (Extended Release): 15 and 30 mg.

DRUG INTERACTIONS: Cyclobenzaprine is chemically related to the tricyclic class of antidepressants (for example, amitriptyline [ Elavil, Endep], nortriptyline [ Pamelor]). As such, it should not be taken with or within two weeks of any monoamine oxidase (MAO) inhibitor, for example, isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), and procarbazine (Matulane). High fever, convulsions, and even death can occur when these drugs are used together. Additionally, cyclobenzaprine interacts with other medications and drugs that slow the brain's processes, such as alcohol, barbiturates, benzodiazepines (for example, diazepam [Valium], lorazepam [ Ativan]), and narcotics.

PREGNANCY AND BREASTFEEDING SAFETY: There are no adequate studies of cyclobenzaprine in pregnant women. However, studies in animals suggest no important effects on the fetus. Cyclobenzaprine therefore can be used in pregnancy if the physician feels that it is necessary.

It is not known whether cyclobenzaprine is secreted in milk. However, since it is related to the tricyclic antidepressants, some of which are excreted in breast milk, caution is advised in using this medication in women who are breastfeeding.

STORAGE: Tablets should be stored between 15 C - 30 C (59 F - 86 F).

DOSING: The recommended dose of cyclobenzaprine dose is 5 or 10 mg three times daily using immediate release tablets or 15 or 30 mg once daily using extended release tablets.

DRUG CLASS AND MECHANISM: Cyclobenzaprine is a muscle relaxant. Specifically, cyclobenzaprine relieves muscle spasm when the spasm is due to local problems, that is, in the muscle itself and not in the nerves controlling the muscles. Cyclobenzaprine has no effect on muscle function. Cyclobenzaprine seems to accomplish its beneficial effect through a complex mechanism within the nervous system, probably in the brainstem. The FDA approved cyclobenzaprine in August 1977.

Medically reviewed by Eni Williams, PharmD

Reference: FDA Prescribing Information

Medically Reviewed by a Doctor on 3/29/2016

Quick GuideChronic Pain: Causes, Solutions and Management

Chronic Pain: Causes, Solutions and Management
FDA Logo

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

RxList Logo

Need help identifying pills and medications?

Use the pill identifier tool on RxList.

Subscribe to MedicineNet's Newsletters

Get the latest health and medical information delivered direct to your inbox!

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

Health Solutions From Our Sponsors