What is the dosage of cyclobenzaprine (a muscle relaxant)?

Cyclobenzaprine Dosage Recommendations

For most patients, the recommended dosage of cyclobenzaprine is 5 mg three times a day, which can be increased to 10 mg three times a day based on individual patient response. 1

Standard Dosing

• The FDA-approved dosage for cyclobenzaprine is 5 mg three times daily, which can be titrated up to 10 mg three times daily if needed 1
• Treatment duration should not exceed two to three weeks 1
• Cyclobenzaprine 5 mg TID is as effective as 10 mg TID but is associated with a lower incidence of sedation 2
• The onset of relief is typically apparent within 3-4 doses of the 5 mg regimen 2

Special Populations

• For elderly patients, less frequent dosing should be considered due to increased risk of adverse effects 1
• For patients with mild hepatic impairment, start with 5 mg and titrate slowly upward 1
• Cyclobenzaprine is not recommended for patients with moderate to severe hepatic insufficiency due to lack of data 1

Efficacy and Mechanism of Action

• Cyclobenzaprine is effective in improving muscle spasm, reducing local pain and tenderness, and increasing range of motion in acute, painful musculoskeletal conditions 2
• The muscle relaxant effect appears to work through activation of locus coeruleus neurons, leading to increased noradrenaline release in the ventral horn of the spinal cord 3
• Clinical trials have demonstrated that cyclobenzaprine is significantly superior to placebo in relieving signs and symptoms of acute skeletal muscle spasm 4

Adverse Effects and Considerations

• Sedation and dry mouth are the most common adverse effects and are dose-related 2
• Over 30% of patients experience drowsiness and sedative-hypnotic effects 5
• The sedative effect is likely due to cyclobenzaprine's non-competitive antagonism at histamine H1 receptors 5
• Combination therapy with cyclobenzaprine 5 mg TID plus ibuprofen has not been shown to be superior to cyclobenzaprine 5 mg TID alone in treating acute neck and back pain with muscle spasm 6

Important Clinical Pearls

• Efficacy of cyclobenzaprine appears to be independent of its sedative effects 2
• Lower doses (2.5 mg TID) have not been shown to be significantly more effective than placebo 2
• Cyclobenzaprine represents a cost-effective approach to managing acute muscle spasm due to its rapid symptomatic relief 4
• Cyclobenzaprine does not provide sedation, analgesia, or amnesia on its own, so it should be administered with appropriate analgesics if pain control is needed 7