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Taking cyclobenzaprine (Amrix, Fexmid, Flexeril) with other substances can result in interactions occurring. Anyone considering this drug first needs to disclose any and all prescription and over-the-counter medications, supplements, herbals, special dietary choices, medical conditions, and substance use to their doctor. This way, the prescribing physician can better decide if cyclobenzaprine is the right choice for managing a patient’s rheumatoid arthritis.

Drug Interactions

Drug interactions may occur with concomitant (at-the-same-time) use of cyclobenzaprine and the following medications:

  • Monoamine oxidase (MAO) inhibitors
  • Barbiturates
  • Central nervous system (CNS) depressants
  • Tramadol
  • Anticholinergic medications
  • Drugs that affect QT-interval
  • Serotonergic agents

Note that this list may not be complete.

Serotonin Syndrome Risk

According to the U.S. National Library of Medicine, concomitant use of this drug along with but not limited to:

  • MAO inhibitors,
  • selective serotonin reuptake inhibitors (SSRIs),
  • serotonin norepinephrine reuptake inhibitors (SNRIs),
  • tricyclic antidepressants (TCAs),
  • tramadol (Ultram),
  • bupropion (Wellbutrin XL, Wellbutrin SR, Forfivo XL, Aplenzin, Zyban),
  • meperidine (Demerol), and
  • verapamil (Verelan, Verelan PM, Calan, Calan SR)

may increase the risk of serotonin syndrome, a potentially life-threatening condition.

Cyclobenzaprine and Tylenol

Tylenol (acetaminophen) is a popular over-the-counter analgesic (pain reliever). It is typically safe to use these medications together however consult your physician for possible pain relief options.

Cyclobenzaprine and Xanax

Xanax (alprazolam) is a widely used sedative. Considering both drugs can depress the central nervous system (CNS), concomitant use may lead to enhanced symptoms of CNS depression, including but not limited to dizziness, trouble breathing, and drowsiness.

Cyclobenzaprine and Aleve

One randomized trial published in JAMA examined emergency department visits for sudden lower back pain; researchers found that combined therapy of naproxen (Aleve) and cyclobenzaprine provided no greater pain relief or improvement in function than that of naproxen and a placebo.

However, a smaller study published in Clinical Therapeutics found that a combination of both cyclobenzaprine and naproxen in treating short-term lower back pain with muscle spasms lead to “less objective muscle spasm and tenderness and greater motion of the lumbosacral spine.” Although, this combination therapy did come with a greater risk of side effects (mostly drowsiness) compared to naproxen use alone.

Cyclobenzaprine and Tramadol

Concomitant use of these medications can result in the potential fatal condition serotonin syndrome, where too much serotonin floods the CNS. Concomitant use of these medications can also lead to CNS depression.

Cyclobenzaprine and Gabapentin

Gabapentin (Gralise, Neuraptine, Horizant, Neurontin) is an anticonvulsant (anti-seizure) and nerve pain medication that may result in central nervous system (CNS) depression or respiratory system depression. Combining both gabapentin and cyclobenzaprine may lead to a synergistic effect, increasing risk of CNS and/or respiratory depression and their symptoms.

Cyclobenzaprine and Zoloft (Sertraline)

Concomitant use of these medications may lead to an increased risk of serotonin syndrome, a potentially life-threatening condition, since both drugs may increase the body’s levels of this neurotransmitter. This combination can also have effects on QT- interval.

Cyclobenzaprine and Lexapro (Escitalopram)

Concomitant use of these medications may lead to an increased risk of serotonin syndrome, a potentially life-threatening condition, since both drugs may increase the body’s levels of this neurotransmitter. This combination can also have effects on QT- interval.

Cyclobenzaprine and Alcohol

For more information, please see our page regarding cyclobenzaprine and alcohol.

Disease and Conditions Interactions

Conditions where the use of cyclobenzaprine is contraindicated, recommended only when absolutely necessary, and/or should be used cautiously include but not limited to:

  • Heart problems
  • Thyroid problems
  • Pregnancy
  • Advanced age
  • Urinary retention problems
  • Glaucoma
  • Increased intraocular pressure (high eye pressure)
  • Liver impairment
  • Breathing problems

Note that this list may not be complete.

Cyclobenzaprine and Pregnancy

For more information, please visit our page regarding pregnancy and cyclobenzaprine.

Food Interactions

Foods and drinks that may possibly interact with this drug include:

  • Alcohol
  • Tobacco

Note that this list may not be complete.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.


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