A patient falls from left lateral excursion causing 5+ mm passive stretch pain. The best initial medication for this TMJ myofascial pain is:

Correct answer: A. Cyclobenzaprine (muscle relaxant — first-line pharmacotherapy for myofascial pain)

• A. Correct. For TMJ MYOFASCIAL PAIN (muscle pain), cyclobenzaprine (a central-acting muscle relaxant) is a commonly used pharmacological adjunct alongside splint therapy and physical therapy. It reduces muscle spasm and hyperactivity. Combined with NSAIDs (ibuprofen), it provides effective short-term pain control.
• B. Diazepam has muscle relaxant properties but carries higher addiction potential and CNS depression compared to cyclobenzaprine for this indication.
• C. Codeine (opioid) is not appropriate first-line for myofascial TMJ pain — addiction risk without superior efficacy.
• D. Ibuprofen alone addresses inflammation but does not address the muscle spasm component as effectively as the combination with a muscle relaxant.