Last reviewed 2026-04-22 · How we verify

Codeine with acetaminophen

Codeine is an opioid agonist that binds to mu opioid receptors to reduce pain perception, while acetaminophen inhibits prostaglandin synthesis to provide additional analgesic and antipyretic effects.

Codeine is an opioid agonist that binds to mu opioid receptors to reduce pain perception, while acetaminophen inhibits prostaglandin synthesis to provide additional analgesic and antipyretic effects. Used for Mild to moderate pain in pediatric patients.

At a glance

Mechanism of action

Codeine is a weak opioid that acts primarily as a mu receptor agonist in the central nervous system, reducing the transmission and perception of pain signals. Acetaminophen works through a separate mechanism by inhibiting cyclooxygenase (COX) enzymes and reducing prostaglandin production, providing complementary analgesia and fever reduction. The combination provides enhanced pain relief through dual mechanisms of action.

Approved indications

• Mild to moderate pain in pediatric patients

Common side effects

• Drowsiness
• Dizziness
• Constipation
• Nausea
• Respiratory depression

Key clinical trials

• Examining Analgesic Synergy and Efficacy in Trauma Care (PHASE4)
• Paracetamol With or Without Ketoprofen in the Management of Pain for Patients Receiving Brachytherapy (KETOCOL-1304) (PHASE2)
• E7 TCR T Cells for Human Papillomavirus-Associated Cancers (PHASE1, PHASE2)
• Opioid-Free Pain Protocol After Shoulder Arthroplasty (PHASE4)
• Opioid-Sparing Joint Replacement (PHASE3)
• An Artificial Intelligence Driven Approach to Optimize Patient Selection for a Transitional Pain Service (PHASE3)
• Celecoxib for ENT Pain Management (PHASE2)
• Post-Op Pain Control for Prophylactic Intramedullary Nailing. (PHASE3)

Primary sources

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