What is the recommended dosing for cyclobenzaprine (a muscle relaxant)?

Cyclobenzaprine Dosing

The standard recommended dose of cyclobenzaprine is 5 mg three times daily, which can be increased to 10 mg three times daily based on individual response, with treatment duration limited to 2-3 weeks maximum. 1

Standard Dosing Regimen

• Start with 5 mg orally three times daily as the initial dose for most patients 1
• May increase to 10 mg three times daily if needed based on patient response 1
• Duration should not exceed 2-3 weeks of continuous use, as cyclobenzaprine is indicated only for acute musculoskeletal conditions, not chronic pain 1, 2

Dose Selection Evidence

• The 5 mg three times daily regimen is as effective as 10 mg three times daily for acute muscle spasm, with significantly lower sedation rates 3
• The 2.5 mg three times daily dose was not significantly more effective than placebo and should be avoided 3
• Onset of relief occurs within 3-4 doses of the 5 mg regimen 3
• Efficacy is independent of sedation, as meaningful treatment effects occur even in patients who do not report somnolence 3

Special Population Adjustments

• Elderly patients (≥65 years): Use less frequent dosing due to altered pharmacokinetics and anticholinergic effects; cyclobenzaprine appears on the Beers Criteria as potentially inappropriate for older adults 1, 2, 4
• Hepatic impairment: Reduce dosing frequency and start at the lowest effective dose given altered drug metabolism 1, 2

Critical Prescribing Restrictions

• Contraindicated with MAO inhibitors due to risk of serotonin syndrome 2, 4
• Not indicated for chronic musculoskeletal pain - lacks long-term efficacy data and should only be used for acute conditions 2
• Taper over 2-3 weeks when discontinuing after extended use to prevent withdrawal symptoms, though tolerance to therapeutic effects does not develop 2, 4

Extended-Release Formulation

• An extended-release formulation exists at 30 mg once daily, providing comparable systemic exposure to 10 mg three times daily immediate-release with sustained plasma concentrations over 24 hours 5, 6
• The extended-release formulation shows a single daily peak versus three peaks with immediate-release 5, 6

Common Adverse Effects

• Sedation and dry mouth are the most common adverse effects, occurring in a dose-dependent manner 3
• Approximately 54-62% of patients on 5-10 mg report at least one adverse event versus 35% on placebo 3
• Adverse events are typically mild in intensity 3, 5