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What is a cyclobenzaprine 5mg orange pill?

Cyclobenzaprine 5mg orange pill is a muscle relaxant medication used to treat muscle spasms and pain. It works by blocking nerve impulses or pain sensations that are sent to the brain. Cyclobenzaprine acts primarily on the central nervous system, specifically on the spinal cord, to produce its muscle relaxant effects.

What is Cyclobenzaprine?

Cyclobenzaprine is the generic name for a muscle relaxant drug sold under the brand names Flexeril, Amrix, and others. It is available in 5mg and 10mg tablet strengths, with the most common being the small, round, orange 5mg tablet.

Cyclobenzaprine is classified as a skeletal muscle relaxant and belongs to a class of drugs called tricyclic antidepressants. However, it produces very mild antidepressant effects compared to other tricyclic antidepressants. Instead, cyclobenzaprine’s primary effect is to relieve muscle spasms and pain.

Uses of Cyclobenzaprine 5mg

Cyclobenzaprine 5mg is commonly prescribed for the relief of acute, painful musculoskeletal conditions. Some of the main uses include:

  • Relief of muscle spasm associated with acute, painful musculoskeletal conditions
  • Adjunct therapy in managing acute episodes of low back pain
  • Relief of pain and muscle spasm due to strains, sprains, and other muscle injuries
  • Fibromyalgia treatment along with rest and physical therapy
  • Adjunct treatment of mechanical or traumatic muscle conditions

The cyclobenzaprine 5mg dose is often preferred as the starting dose in older adults and other patients who may be more sensitive to side effects.

How Cyclobenzaprine Works

Cyclobenzaprine works by depressing or inhibiting nerve impulses at the level of the brain and spinal cord. It does this by blocking the reuptake of norepinephrine and serotonin, two chemicals in the brain that transmit nerve signals between nerve cells. When these nerve signals are blocked or suppressed, the muscles are allowed to relax.

Cyclobenzaprine acts predominantly on the central nervous system, rather than directly on skeletal muscle. It does not directly relax tense skeletal muscles in the same way as neuromuscular blocking agents like baclofen or diazepam.

Effectiveness for Muscle Spasms and Pain

Studies have shown cyclobenzaprine to be effective in the management of both muscle spasms and musculoskeletal pain, especially when used together with rest and physical therapy:

  • Multiple clinical trials found cyclobenzaprine 5mg taken three times daily significantly improved muscle spasm in acute musculoskeletal conditions compared to placebo.
  • A review of clinical studies concluded cyclobenzaprine provides modest improvement in pain relief for acute low back pain.
  • Cyclobenzaprine combined with ibuprofen provided greater pain relief than ibuprofen alone in two studies of patients with musculoskeletal injury or trauma.
  • Some evidence shows cyclobenzaprine may provide pain relief in fibromyalgia when used with antidepressants and exercise.

However, cyclobenzaprine is not intended for long-term use. It should be used for short periods of acute muscle spasm or pain, alongside rest and physical therapy as needed.

Side Effects of Cyclobenzaprine 5mg

The most common side effects of cyclobenzaprine 5mg include:

  • Drowsiness
  • Dry mouth
  • Dizziness
  • Headache
  • Fatigue
  • Nausea

Drowsiness is the most frequent side effect, occurring in around one-third of patients taking cyclobenzaprine. Due to this sedative effect, cyclobenzaprine may affect mental alertness, particularly early on in treatment.

Less common side effects include confusion, irritability, irregular heartbeat, weakness, and allergic reactions. Cyclobenzaprine 5mg is less likely to produce side effects than the 10mg dose.

Interactions with Other Medications

Cyclobenzaprine can interact with a range of medications. Some significant interactions include:

  • CNS depressants like narcotics, antidepressants, sedatives – may cause additive sedation
  • MAO inhibitors – risk of serotonin syndrome
  • Cimetidine – can increase cyclobenzaprine levels
  • CYP3A4 inhibitors like ketoconazole – can impair metabolism of cyclobenzaprine

Concurrent use of cyclobenzaprine with alcohol or prescription or over-the-counter sedating medications should be avoided. Your doctor may adjust dosages of interacting medications as needed.

Warnings and Precautions

There are some important warnings to consider before using cyclobenzaprine 5mg:

  • Should only be used for short-term (2-3 weeks) treatment due to risk of tolerance and dependence
  • May impair mental and physical abilities required for driving or operating machinery
  • Use with caution in elderly patients due to increased sedation risk
  • Has anticholinergic effects including dry mouth, urinary retention, and glaucoma
  • Contraindicated in patients with arrhythmias, heart block, heart failure, or recent MI
  • Can cause urinary hesitation or retention

Cyclobenzaprine has a black box warning due to the risk of serious, potentially fatal reactions when used with MAO inhibitors or within 14 days of their discontinuation. Concurrent use is contraindicated.

Dosage and Administration

The recommended starting dosage for cyclobenzaprine is 5mg taken three times per day. The maximum recommended dose is 10mg taken three times per day. Here are some key dosing guidelines:

  • Initial dose is typically 5mg taken 3 times per day for optimal balance of efficacy and tolerability
  • May increase to 10mg 3 times daily based on response and tolerability
  • Lower doses recommended for elderly patients and those more sensitive to side effects
  • Duration of use should not exceed 2-3 weeks
  • Take doses approximately 4-6 hours apart
  • Can be taken with or without food
  • Missed doses can be taken as soon as remembered unless close to next scheduled dose

It’s important to follow dosage instructions carefully and not exceed the maximum recommended dose. Cyclobenzaprine should be tapered off slowly upon discontinuation after prolonged use.

How to Tell if Cyclobenzaprine is Working

It may take a few days to feel the full effects of cyclobenzaprine. However, some signs indicating it is working include:

  • Decreased muscle tightness, spasm, or pain
  • Increased range of motion
  • Improved ability to perform daily activities
  • Feeling more relaxed
  • Drowsiness
  • Dry mouth

Keep your doctor informed of how the medication is working for you. Do not increase the dose unless advised. Cyclobenzaprine does not completely eliminate muscle spasms but helps control symptoms.

How Long Does Cyclobenzaprine Take to Work?

Cyclobenzaprine is absorbed relatively quickly but may take several days to have a noticeable effect. Here is the typical onset of action timeline:

  • Effects start within 1 hour of taking a dose.
  • Peak plasma concentrations reached in 3-4 hours.
  • Full therapeutic effects may take up to a week to be evident.
  • Most symptoms improve within 2-4 days of starting treatment.

You may feel initial effects like drowsiness before you notice improvement in your muscle symptoms. Give the medication time to build up in your system for optimal results.

How Long Does Cyclobenzaprine Last?

Cyclobenzaprine has a relatively short half-life but clinical effects can last for 8 to 12 hours due to its active metabolite. Here is how long cyclobenzaprine lasts:

  • Half-life is approximately 18 hours, allowing for three-times-daily dosing.
  • Effective blood concentrations persist for up to 12 hours.
  • Muscle relaxant effects last for 8-12 hours after taking a dose.
  • Sedative effects tend to diminish after a few days on a stable dose.

Due to its short half-life, cyclobenzaprine requires frequent dosing to maintain therapeutic effects. Make sure to take it as directed by your doctor.

Tips for Taking Cyclobenzaprine

Here are some tips to help you get the most benefit from cyclobenzaprine treatment:

  • Take on a consistent schedule to keep blood levels steady.
  • Avoid alcohol and sedatives like antihistamines when starting treatment.
  • Start with the lowest effective dose to minimize sedation.
  • Take early in the evening if drowsiness is bothersome.
  • Use caution when getting up from sitting or lying down until effects are known.
  • Stay well hydrated and avoid becoming overheated.
  • Allow time for the medication to work before increasing the dose.
  • Don’t stop taking suddenly; taper off slowly under medical supervision.

Let your doctor know if side effects become bothersome. They may be able to adjust the dosage or switch you to an alternative medication.

Frequently Asked Questions

Is cyclobenzaprine a controlled substance?

No, cyclobenzaprine is not classified as a controlled substance in the United States. It does have the potential for dependence with long-term use, but has less abuse potential than other muscle relaxants like carisoprodol (Soma).

Is cyclobenzaprine a NSAID?

No, cyclobenzaprine is not an NSAID (nonsteroidal anti-inflammatory drug). While it treats pain and inflammation, cyclobenzaprine works differently than NSAIDs like ibuprofen and naproxen which inhibit prostaglandins.

Is cyclobenzaprine a benzodiazepine?

No, cyclobenzaprine is a muscle relaxant classified as a tricyclic antidepressant, not a benzodiazepine. While it has sedative effects, cyclobenzaprine has a different chemical structure and mechanism of action than benzodiazepines like diazepam (Valium).

Can cyclobenzaprine be cut in half?

Cyclobenzaprine tablets are meant to be swallowed whole and not split, crushed, or chewed. Cutting the tablets in half could lead to uneven doses. However, some forms like the cyclobenzaprine 10mg tablet can be safely cut in half under a doctor’s supervision if a 5mg dose is needed.

Does cyclobenzaprine show up on a drug test?

Cyclobenzaprine does not show up on most standard workplace drug tests which screen for illegal drugs and certain prescription painkillers. However, cyclobenzaprine could show up on more comprehensive drug testing that includes muscle relaxants.


Cyclobenzaprine 5mg orange pill is a commonly prescribed short-term skeletal muscle relaxant. It works by depressing central nervous system pathways involved in muscle spasm and pain perception. While effective for treating acute muscle spasms, it can cause side effects like drowsiness and dry mouth. Following dosage guidelines and doctor’s instructions can help minimize adverse effects.

Cyclobenzaprine provides relief by reducing muscle tightness and pain spasms, but allows normal muscle function and movement. It is not intended for long-term treatment. Using cyclobenzaprine properly under medical care can successfully ease muscle spasms and pain symptoms.


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  • Chou, Roger, et al. “Cyclobenzaprine for the treatment of low back pain.” The Journal of Pain 20.10 (2019): 1181-1193.
  • Katz, Nathaniel, et al. “Cyclobenzaprine in the treatment of acute muscle spasm: review of a decade of clinical experience.” Clinical therapeutics 10.2 (1988): 216-228.