What Is Cyclobenzaprine? Uses, Dosage, and What You Need to Know in 2026

Cyclobenzaprine Is a Prescription Muscle Relaxant Used to Treat Muscle Spasms

Cyclobenzaprine is a centrally acting skeletal muscle relaxant prescribed to relieve muscle spasms associated with acute, painful musculoskeletal conditions like back strains, neck injuries, and sprains.

It's one of the most commonly prescribed muscle relaxants in the United States and has been in use for decades. Whether you've just been prescribed Cyclobenzaprine or you're researching it, this guide covers everything you need to know — from how it works to what it costs in 2026.

What Is Cyclobenzaprine?

Cyclobenzaprine is the generic name for a prescription muscle relaxant. You might also know it by these brand names:

• Flexeril — the original brand name (now discontinued)
• Amrix — an extended-release capsule formulation
• Fexmid — another brand (discontinued)
• Tonmya — a sublingual formulation approved in 2024 for fibromyalgia

Cyclobenzaprine belongs to the class of centrally acting skeletal muscle relaxants. Interestingly, it's structurally related to tricyclic antidepressants like Amitriptyline — though it's not used as an antidepressant.

It was originally FDA-approved for short-term use (2 to 3 weeks) as part of a treatment plan that includes rest and physical therapy for relief of muscle spasms.

Cyclobenzaprine is not a controlled substance under the Controlled Substances Act. It does not have a DEA schedule, which means it's easier to prescribe and fill than scheduled medications.

What Is Cyclobenzaprine Used For?

FDA-Approved Use

Cyclobenzaprine is FDA-approved as an adjunct to rest and physical therapy for the relief of muscle spasm associated with acute, painful musculoskeletal conditions. This includes:

• Back strains and sprains
• Neck pain with muscle spasm
• Muscle injuries from accidents or overexertion

Off-Label Uses

Doctors sometimes prescribe Cyclobenzaprine for conditions beyond its official approval, including:

• Fibromyalgia — particularly for associated insomnia and sleep problems
• Myofascial pain from temporomandibular disorders (TMJ)
• Chronic low back pain
• Tension headaches

Off-label prescribing is legal and common when a doctor believes the medication will benefit you based on available evidence.

How Is Cyclobenzaprine Taken?

Cyclobenzaprine comes in two forms:

Immediate-Release Tablets

• Strengths: 5 mg, 7.5 mg, and 10 mg
• Typical dose: 5 mg three times daily, which may be increased to 10 mg three times daily
• Maximum dose: 30 mg per day
• How to take: With or without food, three times daily

Extended-Release Capsules (Amrix)

• Strengths: 15 mg and 30 mg
• Typical dose: 15 mg once daily; some patients may need 30 mg once daily
• Maximum dose: 30 mg per day
• How to take: Once daily at the same time each day. Do not crush, chew, or open the capsules.

Important: Cyclobenzaprine is meant for short-term use — typically 2 to 3 weeks. Your doctor will reassess whether you still need it after this period.

For more on how it works in your body, see our guide on how Cyclobenzaprine works.

Who Should Not Take Cyclobenzaprine?

Cyclobenzaprine is not appropriate for everyone. You should not take it if you have:

• Hypersensitivity to Cyclobenzaprine or any ingredient in the formulation
• Used an MAO inhibitor (such as Phenelzine, Tranylcypromine, or Selegiline) within the past 14 days — combining these can cause a life-threatening reaction
• Recent heart attack (acute recovery phase)
• Cardiac arrhythmias, heart block, or conduction disturbances
• Heart failure
• Hyperthyroidism (overactive thyroid)

Use with caution if you:

• Are over 65 years old (Cyclobenzaprine is on the Beers Criteria list for potentially inappropriate medications in older adults)
• Have liver problems (start at a lower dose; not recommended for moderate-to-severe hepatic impairment)
• Are pregnant or breastfeeding (Category B — use only if clearly needed)
• Are under 15 years old (not recommended)

Always tell your doctor about all medications you take, including over-the-counter drugs and supplements. Cyclobenzaprine has important drug interactions that can be dangerous.

How Much Does Cyclobenzaprine Cost?

Cost depends on which form you're prescribed and whether you have insurance:

Generic Immediate-Release Tablets

• Without insurance or coupons: $10 to $35 for 30 tablets (5 mg or 10 mg)
• With coupons (GoodRx, SingleCare, etc.): As low as $4 to $9 for 30 tablets
• With insurance: Typically Tier 1 (preferred generic) with copays of $0 to $15

Generic Extended-Release Capsules

• Without insurance: Average retail around $1,067 for 30 capsules (15 mg)
• With coupons: Around $54 for 30 capsules
• With insurance: May require prior authorization; some plans require trying IR first (step therapy)

Brand Amrix

• Without insurance: $300 to $1,000+ for 30 capsules

The takeaway: generic immediate-release Cyclobenzaprine is very affordable. Always ask your pharmacy to fill the generic unless your doctor specifies otherwise. For the best prices and coupons, check out our guide to saving money on Cyclobenzaprine.

Final Thoughts

Cyclobenzaprine is a well-established, effective muscle relaxant that's been helping patients manage acute muscle pain for decades. It's affordable in its generic form, widely available, and can be prescribed by most doctors — including through telehealth.

The key things to remember:

• It's meant for short-term use (2 to 3 weeks)
• Drowsiness is the most common side effect
• It should not be taken with MAO inhibitors or if you have certain heart conditions
• Generic IR tablets are very affordable, often under $10 with a coupon

If you're having trouble finding Cyclobenzaprine at your pharmacy, use Medfinder to check stock near you. And if your doctor is considering alternatives, review our guide on alternatives to Cyclobenzaprine.