Mixing Xanax & Cyclobenzaprine What Amounts are Safe

Sometimes, a physician may prescribe Xanax and cyclobenzaprine at the same time.


Flexeril (cyclobenzaprine) is a muscle relaxant that is primarily prescribed to relieve muscle spasms and/or pain and stiffness occurring from musculoskeletal conditions.

It does not appear to be effective for muscle spasms due to central nervous system disorders like multiple sclerosis or a brain injury.

It may also be used to treat various types of headaches, insomnia, and tinnitus, although these are off-label uses.

Flexeril is prescribed for short-term use only. It is used in conjunction with physical therapy because tolerance to the drug develops rapidly.

It becomes ineffective as a muscle relaxant after a few weeks of use.


Xanax (alprazolam) is a benzodiazepine drug and one of the most commonly prescribed medications in the United States. It is primarily designed as a treatment for anxiety, as a sleep enhancer, or as a muscle relaxant. It may less often be used to treat seizures or as a preanesthetic.
Xanax should only be a short-term solution to clinically significant anxiety, insomnia, or other similar issues due to the rapid development of tolerance to the effects of the drug

Availability & Status

Flexeril is not a controlled substance, but it does require a prescription. Xanax is a controlled substance listed in the Schedule IV classification (CIV).
The continued use of either substance will produce tolerance, and abrupt discontinuation will produce a withdrawal syndrome; however, the withdrawal syndrome associated with benzodiazepines like Xanax is typically far more severe than the withdrawal that may occur from cyclobenzaprine.

Comparing Mechanisms of Action

Although both drugs produce sedation, relaxation, and anxiety relief — Xanax is far more powerful for relieving anxiety. However,  they have entirely different mechanisms of action.

Glass of Whiskey surrounded by Assorted Pills

Flexeril works similarly to a group of antidepressants known as tricyclicantidepressants.

It is believed to affect the action of the neurotransmitter acetylcholine, which is involved in muscular movements. It is thought to block the action of acetylcholine, leading to its ability to produce relaxation and relieve muscle spasms.

Xanax affects the major inhibitory neurotransmitter in the brain, gamma-aminobutyric acid (GABA). By increasing the availability of GABA in the brain and spinal cord, Xanax use reduces the firing of neurons in the central nervous system. This leads to its ability to reduce anxiety, induce sedation, and act as a muscle relaxant.

Use & Misuse

According to data provided by the Substance Abuse and Mental Health Services Administration (SAMHSA):

  • In 2016, it was estimated that 5.2 million people used cyclobenzaprine at least once.
  • In 2016, it was estimated that 18.4 million individuals used alprazolam (Xanax) at least once.
  • In 2017, it was estimated that 4.8 million individuals used cyclobenzaprine at least once.
  • In 2017, it was estimated that nearly 18 million individuals used alprazolam at least once,.

The data indicate that Xanax is far more used than cyclobenzaprine, but also that the percentage of people admitting to misusing Xanax is much higher than the rate of people who admit to misusing Flexeril. This reflects the higher potential for benzodiazepines as drugs of abuse and their status as controlled substances.
Whenever someone is using a benzodiazepine, their physician should monitor them closely and pay attention to any other drugs they are prescribed or using. Signs of abuse should be noted, and the physician should act accordingly if abuse is suspected for any prescription medication.

What Are the Effects of Mixing Flexeril With Xanax?

Both Xanax and cyclobenzaprine produce sedating effects. When drugs that have similar effects are mixed, the result is an enhancement of the effects of both drugs.
When alprazolam and cyclobenzaprine are used together, the result is typically an increase in the side effects associated with these drugs in addition to increased levels of sedation. These enhanced effects could include:

  • Increased feelings of drowsiness
  • Increased feelings of drowsiness
  • Increased problems concentrating and remembering new information
  • Possible confusion
  • Reduced response times and altered motor coordination
  • Significant impairment in thinking, judgment, and reasoning abilities in some people.

Limitations When Taking Both Medications

There are several limitations when someone is using both of these medications together.

  • Certain types of foods might need to be limited, such as grapefruit juice.
  • Other medications may need to be reduced or eliminated.
  • It is generally advised not to drive or use machinery while under the influence.
  • If the person notices any significant unexpected or unusual reactions as a result of using these medications, they should stop use and contact their physician.

Abusing Xanax & Flexeril

Combining Xanax and Flexeril for recreational use (abuse) could be particularly dangerous because of the enhancement of effects. Combining these drugs in high amounts can lead to certain results that can be potentially serious, including:

  • A significant slowing of breath rate, heart rate, and blood pressure.
  • Significant problems with consciousness and alertness
  • A noteworthy effect on judgment that can lead to serious problems.
  • Significantly decreased coordination that can be potentially dangerous.

The enhancement of the effects that can occur as a result of abuse can lead to the increased potential for an overdose on either drug, which can be fatal



Is It Safe to Combine Xanax & Cyclobenzaprine?

Because the drugs have different mechanisms of action, they sometimes may be prescribed in combination. However, only a physician can make these drugs safely available to anyone in combination.
Individuals should not use these drugs together if they are not under the supervision of a physician. Physicians understand the safe amounts of medications that can be used together, and individuals who abuse drugs do not.