CYCLOBENZAPRINE is a muscle relaxant. It works by blocking nerve impulses (or pain sensations) that are sent to your brain. Cyclobenzaprine is used together with rest and physical therapy to treat skeletal muscle conditions such as pain or injury. Cyclobenzaprine may also be used for purposes not listed in this medication guide.

Do not use cyclobenzaprine if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine. You should not use cyclobenzaprine if you are allergic to it, or if you have: a heart rhythm disorder, or you have recently had a heart attack; congestive heart failure; heart block; or a thyroid disorder. To make sure cyclobenzaprine is safe for you, tell your doctor if you have: liver disease; glaucoma; enlarged prostate; or problems with urination. Older adults may be more sensitive to the side effects of this medication.

Cyclobenzaprine is usually taken once daily for only 2 or 3 weeks. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended. Take the medicine at the same time each day. Do not crush, chew, break, or open an extended-release capsule. Swallow it whole. You may have unpleasant withdrawal symptoms when you stop taking cyclobenzaprine after long-term use. Ask your doctor how to avoid withdrawal symptoms when you stop using this medicine. Cyclobenzaprine is only part of a complete program of treatment that may also include rest, physical therapy, or other pain relief measures. Follow your doctor's instructions. Store at room temperature away from moisture, heat, and light.

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

Taking cyclobenzaprine with other drugs that make you sleepy or slow your breathing can cause dangerous or life-threatening side effects. Ask your doctor before taking cyclobenzaprine with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures. This list is not complete. Other drugs may interact with cyclobenzaprine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.