Cyclobenzaprine is a skeletal muscle relaxant that has been prescribed since 1977 for the muscle spasm that goes with a strained back or neck. Chemically it is a close relative of the tricyclic antidepressant amitriptyline, which explains both how it works, in the brain stem rather than in the muscle, and its best-known side effects, drowsiness and a dry mouth.
In the United States cyclobenzaprine is FDA-approved as 5, 7.5, and 10 mg tablets and as 15 and 30 mg extended-release capsules, for muscle spasm from acute, painful musculoskeletal conditions, as an adjunct to rest and physical therapy, for up to two or three weeks. No cyclobenzaprine gel, cream, oral liquid, or troche is manufactured, so when a prescriber orders one, Bayview compounds cyclobenzaprine hydrochloride in that form and strength. These compounded preparations are not FDA-approved, their use is off-label, and a valid prescription is required. Bayview compounds this as part of our pain management line.
How does it work?
Cyclobenzaprine does not act on the muscle fiber. It works in the brain stem, where it reduces the nerve activity that keeps a muscle in spasm, mainly by blocking serotonin 5-HT2 receptors and by effects on the motor pathways that run from the brain to the spinal cord (StatPearls, Cyclobenzaprine). Because its structure is so close to a tricyclic antidepressant, it also blocks acetylcholine and histamine receptors, which is where the dry mouth and drowsiness come from (DailyMed, cyclobenzaprine tablets label). Applied as a gel, some of the dose is taken up by the skin and underlying tissue and some enters the circulation; how much depends on the strength, the area treated, and the base.
What is it used for?
The approved use of the tablets is muscle spasm from an acute, painful musculoskeletal condition, a strained back or neck for example, together with rest and physical therapy, for a short course of up to two or three weeks (DailyMed, cyclobenzaprine tablets label). Prescribers also use cyclobenzaprine off-label for the sleep disturbance of fibromyalgia and for jaw pain from temporomandibular joint disorders (StatPearls, Cyclobenzaprine). The compounded gel is ordered for the same kinds of problems when a prescriber wants the medicine at the painful muscle instead of a tablet that sedates the whole patient: a localized spasm, a stiff neck or low back, a myofascial trigger point, or a tender jaw. The evidence here is thin. In a randomized trial of 399 patients, a compounded cream for muscle and joint pain that combined cyclobenzaprine with ketoprofen, baclofen, and lidocaine was not better than a placebo cream at one month (Brutcher et al., 2019), and no trial of a single-agent cyclobenzaprine gel was identified. Your prescriber weighs that when deciding whether it fits your situation.
Gel, cream, or by mouth?
The gel is prepared in an anhydrous base in a metered pump, so each press delivers about the same amount, and it is rubbed into the skin over the painful muscle; a cream base can be prepared on request for patients who prefer it. The oral liquid is measured with a syringe and is for people who cannot swallow tablets or need a dose smaller than the 5 mg tablet; the troche dissolves in the mouth; custom capsules are for a strength or an ingredient list the manufactured tablets do not offer. Your prescriber selects the form and strength; see the strengths section for what Bayview compounds.
How is it used?
Follow the directions on your label exactly. For the gel, apply the number of pumps your prescriber named to clean, dry, unbroken skin over the painful muscle, rub it in, and wash your hands afterward; keep it away from your eyes and mouth, and do not cover the area unless you were told to. Use it no more often, and for no longer, than the label says; the tablets are approved for two or three weeks, and a gel is not a reason to extend that. Do not drive or do anything hazardous until you know whether it makes you drowsy, and do not drink alcohol while using it (MedlinePlus, Cyclobenzaprine). If you miss a dose of the oral forms, take it when you remember unless the next dose is near, and never double up.
Side effects & safety
Drowsiness and dry mouth are the most common effects. In the tablet trials, drowsiness was reported by 29% of patients on 5 mg and 38% on 10 mg, against 10% on placebo, and dry mouth by 21% and 32%, against 7% (DailyMed, cyclobenzaprine tablets label). Dizziness, fatigue, headache, nausea, and constipation follow. The gel is expected to produce less of these than a tablet, because less reaches the bloodstream, but it can still cause them, and it can redden or itch the skin where it is applied.
Who should not use it?
Do not use cyclobenzaprine if you have taken an MAOI in the past 14 days, are recovering from a heart attack, have an irregular heartbeat, heart block, or heart failure, have hyperthyroidism, or are allergic to it. Talk with your prescriber before using it if you have liver disease, glaucoma, an enlarged prostate or trouble urinating, or if you take an antidepressant, tramadol, or another sedating medicine, or if you are 65 or older. Tell your prescriber if you are pregnant or breastfeeding: the amounts in breast milk appear to be very small and two breastfed infants tolerated it well, but the infant should be watched for drowsiness (LactMed, Cyclobenzaprine). Safety in children under 15 has not been established (DailyMed, cyclobenzaprine tablets label).
How should it be stored?
Store as directed on your label, at room temperature away from heat, light, and moisture, with the pump closed, and keep it out of the reach of children and pets. Do not use it after the beyond-use date, and dispose of unused medication as directed.
Why is this compounded?
The manufactured cyclobenzaprine products are tablets and extended-release capsules. When a prescriber wants the medicine applied to one muscle instead of swallowed, a liquid dose for a patient who cannot take tablets, a troche, or a strength the tablets do not come in, compounding is the only way to prepare it. As a 503A compounding pharmacy, Bayview prepares each order in small batches under USP standards, pursuant to a prescription for an individual patient. We do not supply it as clinic or office stock, that is the role of a 503B outsourcing facility, which Bayview is not. Compounded preparations are not FDA-approved. Related preparations include Topical Pain Cream, Diclofenac Gel, and Lidocaine Cream & Ointment. The full list is in our compounded medications catalog.
Clinical details for prescribers
Regulatory status. Cyclobenzaprine hydrochloride, a centrally acting skeletal muscle relaxant structurally related to the tricyclic antidepressants. FDA-approved presentations: 5, 7.5, and 10 mg immediate-release tablets (5 mg three times daily, may be increased to 10 mg three times daily; maximum 30 mg/day) and 15 and 30 mg extended-release capsules, indicated as an adjunct to rest and physical therapy for muscle spasm associated with acute, painful musculoskeletal conditions, for periods of up to 2 or 3 weeks. Compounded topical gel and cream, oral liquid, troches, and capsules are 503A preparations, not FDA-approved, and off-label. Not a controlled substance.
Formulation & directions. Bayview compounds cyclobenzaprine HCl as 0.5%, 1%, 2% (20 mg/g), and 5% topical gel in an anhydrous gel base (metered pump, 30 to 100 g), the same strengths in a cream base on request, 1 and 2 mg/mL oral liquid, 10 mg troches, and custom-strength capsules. Typical directions: gel, 1 to 2 pumps to the affected muscle two to three times daily for up to 14 days, not on broken skin; oral liquid, 2.5 to 5 mg three times daily. Specify a duration on every prescription. Combination gels (ketoprofen, diclofenac, baclofen, gabapentin, lidocaine) are separate preparations ordered on the topical pain cream form.
Safety & counseling:
- Contraindications: MAOI within 14 days, acute recovery phase of MI, arrhythmias, heart block or conduction disturbances, congestive heart failure, hyperthyroidism, hypersensitivity. Warnings: serotonin syndrome with SSRIs, SNRIs, TCAs, tramadol, meperidine, bupropion, verapamil; tricyclic-like cardiac effects; additive CNS depression with alcohol and sedatives; anticholinergic effects (urinary retention, angle-closure glaucoma) (DailyMed, cyclobenzaprine tablets label).
- Adverse reactions in the tablet trials: drowsiness 29% (5 mg) and 38% (10 mg) vs 10% placebo; dry mouth 21% and 32% vs 7%; fatigue 6% vs 3%. Systemic exposure from a topical gel is uncounted but not zero; counsel on driving and alcohol regardless of route (DailyMed, cyclobenzaprine tablets label).
- Beers criteria: avoid in patients 65 and older (sedation, confusion, falls). Hepatic impairment: start 5 mg and titrate in mild impairment; not recommended in moderate or severe. Avoid in advanced CKD (StatPearls, Cyclobenzaprine).
- Evidence for topical use: in a randomized, placebo-controlled trial of 399 patients with localized chronic pain, the nociceptive-pain cream (ketoprofen 10%, baclofen 2%, cyclobenzaprine 2%, lidocaine 2%) did not reduce average pain more than placebo at one month (-0.3 points, 95% CI -0.9 to 0.2); no trial of single-agent topical cyclobenzaprine was identified. Frame expectations accordingly (Brutcher et al., 2019).
- Pregnancy: animal data reassuring, human data limited. Lactation: milk levels appear very small; monitor the infant for drowsiness (LactMed, Cyclobenzaprine). Pediatric safety and effectiveness not established under 15 years.
Non-controlled; ship to patient or office per the order form. Licensed to dispense in RI, MA, CT, NY, NJ, NH, and FL. Background: DailyMed, cyclobenzaprine tablets label; StatPearls, Cyclobenzaprine; Brutcher et al., 2019; LactMed, Cyclobenzaprine. Account setup, licensing, and ordering are covered on our for providers page.
This is a prescription compounded medication and is not FDA-approved; its use is off-label. This information is educational and is not medical advice. Your prescriber determines whether it is appropriate and sets the formulation and directions.
