Would you use Flexeril (cyclobenzaprine) for rib pain?

Cyclobenzaprine for Rib Pain

I would not recommend cyclobenzaprine (Flexeril) for rib pain, as it is FDA-approved only for muscle spasm associated with acute musculoskeletal conditions, not for rib fractures, and the American Geriatrics Society specifically recommends avoiding it in elderly patients due to significant anticholinergic effects and fall risk. 1, 2

Why Cyclobenzaprine Is Not Appropriate for Rib Pain

• Cyclobenzaprine is indicated only for muscle spasm associated with acute, painful musculoskeletal conditions—not for bone pain or rib fractures 2
• Rib pain typically results from fracture, contusion, or inflammation of the rib cage itself, not from true muscle spasm that would respond to muscle relaxants 3
• The American Geriatrics Society lists cyclobenzaprine in the Beers Criteria as potentially inappropriate for older adults due to its structural similarity to tricyclic antidepressants, causing CNS impairment, delirium, slowed comprehension, and increased fall risk 1
• Most muscle relaxants, including cyclobenzaprine, have no evidence of efficacy in chronic pain and do not directly relax skeletal muscle 1

Recommended Treatment Approach for Rib Pain

First-Line Therapy

• Start with scheduled acetaminophen 1000 mg every 6 hours as the foundation of pain management 3
• Oral acetaminophen is equivalent to IV formulations for pain control in rib fractures 3

Second-Line Additions

• Add NSAIDs (such as ketorolac or ibuprofen) if acetaminophen alone is insufficient, but avoid in patients with kidney disease, GI ulcers, or on anticoagulation 3, 4
• Ketorolac can be particularly effective as an adjunct to reduce opioid requirements in moderate to severe rib pain 4

Non-Pharmacological Measures

• Apply ice or cold compresses to the painful area for additional relief 3
• Immobilization techniques and supportive dressings can reduce pain with movement 3

Important Safety Considerations

• If you are over 60 years old with rib pain, you are at significantly higher risk for complications including pneumonia, respiratory failure, and mortality 3, 4
• Seek immediate medical attention if you develop increasing shortness of breath, fever, productive cough, sudden worsening of chest pain, dizziness, fainting, or confusion 3
• Follow up with your physician within 3-5 days if you have risk factors: age >60, chronic lung disease, anticoagulation therapy, or multiple rib fractures 3

Why Muscle Relaxants Are Problematic

• Cyclobenzaprine should be held on the day of any surgical procedure due to interactions with anesthetics 1
• The medication causes significant sedation, which is dose-related and can impair daily function 5
• In studies of low back pain with muscle spasm, adding cyclobenzaprine to naproxen showed no improvement in functional outcomes compared to naproxen alone at 1-week follow-up 6
• All muscle relaxants are associated with greater risk for falls in older persons 1

Expected Recovery Timeline

• Rib fractures typically heal within 6-8 weeks, though complete recovery with resolution of pain may take up to 2 years in some patients with multiple or displaced fractures 3
• Pain scores typically improve significantly by 4 weeks with appropriate management 3
• If pain persists beyond 4-6 weeks, consider physical therapy referral 3