Cyclobenzaprine

Cyclobenzaprine hydrochloride extended-release capsules are indicated as an adjunct to rest and physical therapy for relief of muscle spasm associated with acute, painful musculoskeletal conditions. Improvement is manifested by relief of muscle spasm and its associated signs and symptoms, namely, pain, tenderness, and limitation of motion. Limitations of Use: Cyclobenzaprine hydrochloride extended-release capsules should be used only for short periods (up to two or three weeks) because adequate evidence of effectiveness for more prolonged use is not available and because muscle spasm associated with acute, painful musculoskeletal conditions is generally of short duration and specific therapy for longer periods is seldom warranted.

Cyclobenzaprine relieves skeletal muscle spasm of local origin without interfering with muscle function. Cyclobenzaprine has not been shown to be effective in muscle spasm due to central nervous system disease. In animal models, cyclobenzaprine reduced or abolished skeletal muscle hyperactivity. Animal studies indicate that cyclobenzaprine does not act at the neuromuscular junction or directly on skeletal muscle. Such studies show that cyclobenzaprine acts primarily within the central nervous system at the brain stem as opposed to the spinal cord level, although an overlapping action on the latter may contribute to its overall skeletal muscle relaxant activity. Evidence suggests that the net effect of cyclobenzaprine is a reduction of tonic somatic motor activity, influencing both gamma (γ) and alpha (α) motor systems.

The recommended adult dose for most patients is one cyclobenzaprine hydrochloride 15 mg extended-release capsule taken once daily. Some patients may require up to 30 mg/day, given as one cyclobenzaprine hydrochloride 30 mg extended-release capsule taken once daily or as two cyclobenzaprine hydrochloride 15 mg extended-release capsules taken once daily. It is recommended that doses be taken at approximately the same time each day. Use of cyclobenzaprine hydrochloride extended-release capsules for periods longer than two or three weeks is not recommended. Instruct patients to swallow cyclobenzaprine hydrochloride extended-release capsules intact. Alternatively, the contents of the cyclobenzaprine hydrochloride extended-release capsule may be sprinkled over applesauce and then swallowed. This method is appropriate only for patients able to reliably swallow the applesauce without chewing.

Hypersensitivity to any component of this product. Adverse reactions may include anaphylactic reaction, urticaria, facial and/or tongue swelling, or pruritus. Discontinue cyclobenzaprine hydrochloride extended-release capsules if a hypersensitivity reaction is suspected. Concomitant use of monoamine oxidase (MAO) inhibitors or within 14 days after their discontinuation. Hyperpyretic crisis seizures and deaths have occurred in patients receiving cyclobenzaprine (or structurally similar tricyclic antidepressants) concomitantly with MAO inhibitor drugs.

Serotonin syndrome has been reported with cyclobenzaprine when used in combination with other serotonergic drugs. Cyclobenzaprine is structurally related to tricyclic antidepressants which have been reported to produce adverse cardiovascular effects or CNS depressant effects. Use in the elderly is not recommended. Use in patients with hepatic impairment is not recommended. Use with caution in patients with a history of urinary retention, angle-closure glaucoma, increased intraocular pressure and in patients taking anticholinergic medications

The following clinically significant reactions are described in greater detail, in other sections. Serotonin Syndrome Adverse Cardiovascular Effects Most common adverse reactions (incidence ≥3% in any treatment group and greater than placebo): dry mouth, dizziness, fatigue, constipation, nausea, dyspepsia, and somnolence

Based on its structural similarity to tricyclic antidepressants, cyclobenzaprine hydrochloride extended-release may have life-threatening interactions with MAO inhibitors, may enhance the effects of alcohol, barbiturates, and other CNS depressants, may enhance the seizure risk in patients taking tramadol, or may block the antihypertensive action of guanethidine and similarly acting compounds. Postmarketing cases of serotonin syndrome have been reported during combined use of cyclobenzaprine and other drugs, such as SSRIs, SNRIs, TCAs, tramadol, bupropion, meperidine, verapamil, or MAO inhibitors. MAO Inhibitors: Life-threatening interactions may occur. Serotonergic Drugs: Serotonin syndrome has been reported. CNS Depressants: Effects of alcohol, barbiturates, and other CNS depressants may be enhanced. Tramadol: Seizure risk may be enhanced.

Store at 25°C (77°F), excursions permitted to 15° - 30°C (59° - 86°F).