Description

Overview
Cyclobenzaprine (brand name Flexeril) is a muscle relaxant commonly prescribed for muscle spasms and pain due to musculoskeletal injuries. Unlike NSAIDs, it does not treat inflammation, but instead acts on the central nervous system to reduce muscle tightness.

Mechanism of Action
Cyclobenzaprine works on the brainstem by inhibiting the activity of certain motor neurons, reducing muscle hyperactivity and spasms without directly affecting the muscles themselves. It has a similar chemical structure to tricyclic antidepressants (TCAs) and has mild sedative properties.

Benefits and Indications
• Muscle spasms – Commonly used after injuries like strains and sprains.
• Fibromyalgia – Helps reduce muscle tightness in some cases.
• Post-surgical muscle pain – Can be prescribed for recovery after procedures involving muscle tension.

Possible Side Effects
• Drowsiness and dizziness – Affects alertness, so it is not recommended for use before driving.
• Dry mouth – Due to its TCA-like structure.
• Fatigue and weakness – Can cause lethargy and reduced muscle function.
• Confusion or hallucinations (rare) – In some elderly patients or with high doses.