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Is cyclobenzaprine a controlled substance or addictive?

Medically reviewed by Leigh Ann Anderson, PharmD. Last updated on Dec 15, 2022.

Official answer


No, cyclobenzaprine is not classified as a controlled substance by the DEA and does not have physically addictive or abuse properties like an opioid or benzodiazepine. It is not a narcotic drug. However, as with many drugs, some patients may feel psychologically dependent or experience withdrawal symptoms upon discontinuation of cyclobenzaprine.

Although cyclobenzaprine has not been associated with addiction, abruptly stopping this medication after prolonged use may lead to symptoms such as nausea, headache, and a general sense of feeling unwell (malaise). Ask your healthcare provider if you should slowly stop treatment (taper your dose) rather than abruptly discontinuing, and the best way to do this.

Why do most people take cyclobenzaprine?

  • Cyclobenzaprine is commonly used along with rest and physical therapy to help relieve muscle spasms due to acute, painful musculoskeletal conditions (for example: back pain, neck pain, or spasms associated with bone fractures, or other injuries).
  • It can help to relieve symptoms such as pain, tenderness, limitation of motion, and trouble carrying out normal daily activities (like dressing, bathing, and resting).
  • Cyclobenzaprine may be used "off-label" for fibromyalgia in some patients, meaning it may be prescribed by your doctor for a generally accepted use not specifically approved by the FDA or listed in package labeling.
  • In general, it should be used only for short periods of time (up to 3 weeks). Acute muscle spasm is generally of short duration.

Cyclobenzaprine is a prescription skeletal muscle relaxant that works in the central nervous system. It relieves skeletal muscle spasms without interfering with muscle function. Its chemical structure and how it works is related to the tricyclic antidepressants (TCAs), an older class of medicines used to treat depression, nerve pain, migraine and other conditions.

Can you overdose on cyclobenzaprine?

If you, or someone you are in contact with, experiences an overdose with cyclobenzaprine, call 911, call the Poison Help line at 1-800-222-1222, or get emergency medical care right away. For the suicide and crisis lifeline, call 988 (available 24/7) for free and confidential help.

Overdose deaths with cyclobenzaprine are rare, but may still occur. People who intentionally overdose with cyclobenzaprine may mix it with other substances, such as alcohol or various CNS depressants. Toxicity may develop rapidly and immediate emergency hospital treatment is recommended.

Healthcare providers should contact their local poison control center or the U.S. National Poison Control Center at 1-800-222-1222 (available 24 hours/day, 7 days a week) for the most current information on cyclobenzaprine overdose.

Symptoms of cyclobenzaprine overdose

The most common symptoms of cyclobenzaprine overdose include drowsiness and fast heart beat rate (tachycardia).

Less common effects include tremor, agitation, coma, impaired balance or coordination, high blood pressure, slurred speech, confusion, dizziness, nausea, vomiting, and hallucinations.

Rare but serious overdose effects of cyclobenzaprine are cardiac arrest (heart suddenly and unexpectedly stops pumping blood), chest pain, abnormal heart rhythm, severe low blood pressure, seizures, and neuroleptic malignant syndrome (may include high fever, sweating, unstable blood pressure, stupor, muscular rigidity, and autonomic dysfunction).

Changes in the electrocardiogram (a recording of the heart's electrical activity), particularly in QRS axis or width, are clinically significant indicators of cyclobenzaprine toxicity.

Does cyclobenzaprine make you sleepy?

Yes, cyclobenzaprine is a central nervous system (CNS) depressant and can cause side effects like drowsiness (fatigue), dizziness, or confusion. These side effects may be greatly enhanced if you combine this medicine with alcohol, sleeping pills or anti-anxiety medicine (for example: barbiturates or benzodiazepines), opioid pain medicines, or other CNS depressants.

You should not combine cyclobenzaprine with alcohol or other CNS depressants unless approved by your healthcare provider.

Do not drive, operate machinery, or do other dangerous activities until you know how cyclobenzaprine affects you. Your thinking and physical response times may be slowed.

What are common side effects or warnings?

Tell your doctor if you have a thyroid disorder (hyperthyroidism), heart block, congestive heart failure (CHF), a heart rhythm disorder (arrhythmias), or you have recently had a heart attack. You may not be able to use this medicine.

The most common side effects of cyclobenzaprine include:

  • dry mouth
  • nausea
  • dizziness
  • upset stomach
  • fatigue
  • drowsiness
  • constipation

In the elderly, more frequent or serious side effects can occur with cyclobenzaprine. Therapy in the elderly should be started with a 5 mg dose and titrated slowly upward.

Dose adjustments may be needed in patients with liver impairment.

Be sure that your doctor or pharmacist checks for any possible drug interactions with cyclobenzaprine. This includes prescription, over-the-counter (OTC) medicines, herbals, vitamins and other dietary supplements.

  • Interaction with other drugs that also increase serotonin (such as antidepressants, tramadol, St John's Wort, bupropion, bupropion, meperidine, verapamil, or MAO inhibitors) may cause serotonin syndrome.
  • Symptoms of serotonin syndrome include mental status changes (such as agitation, hallucinations, coma, delirium), fast heart rate, dizziness, flushing, muscle tremor or rigidity, and stomach symptoms (including nausea, vomiting, and diarrhea).
  • Do not use cyclobenzaprine if you have taken an MAO inhibitor in the past 14 days. MAO inhibitors include medicines such as such as isocarboxazid (Marplan), linezolid (Zyvox), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Zelapar), or tranylcypromine (Parnate). This combination could cause serious side effects or be fatal.

These are not all of the common or serious side effects that may occur. If you have questions about side effects, call your doctor for medical advice.

How does cyclobenzaprine come?

  • Cyclobenzaprine is available as a generic 5 mg, 7.5 mg and 10 immediate-release tablet. In general, the generic immediate-release tablet usually costs about $10 to $20 for 30 of the 5 or 10 mg tablets. Prices may differ based on your drug strength, pharmacy, any coupons you have, or location.
  • A brand name extended-release product, Amrix, is also available but is expensive and may not be covered by your insurance. Amrix also comes as a generic, extended-release, once-daily capsule in 15 mg and 30 mg strengths, but is still more expensive than the immediate-release tablets.

Flexeril, a once popular brand name cyclobenzaprine tablet has been discontinued from the US market. You still may hear consumers or healthcare providers refer to cyclobenzaprine as “Flexeril” because it was such a common name.

Use this medicine exactly as directed. This is not all the information you need to know about cyclobenzaprine for safe and effective use and does not take the place of your doctor’s directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider.


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