Last reviewed 2026-04-22 · How we verify

Tylenol Pill

Acetaminophen reduces pain and fever by inhibiting prostaglandin synthesis in the central nervous system.

Acetaminophen reduces pain and fever by inhibiting prostaglandin synthesis in the central nervous system. Used for Mild to moderate pain, Fever reduction.

At a glance

Mechanism of action

Acetaminophen (paracetamol) works primarily through inhibition of cyclooxygenase (COX) enzymes in the brain and spinal cord, reducing the production of prostaglandins that mediate pain and fever signaling. Unlike NSAIDs, it has minimal peripheral anti-inflammatory effects and does not significantly inhibit COX in peripheral tissues, making it gentler on the gastrointestinal tract and cardiovascular system.

Approved indications

• Mild to moderate pain
• Fever reduction

Common side effects

• Hepatotoxicity (at high doses or chronic use)
• Nausea
• Rash

Key clinical trials

• Open-label Placebo (COLP) for Pain in Adolescent Idiopathic Scoliosis (AIS) Surgery+Surgical Treatment of Idiopathic Scoliosis (NA)
• A Research Study Looking Into the Effect of NNC0519-0130 on Blood Levels of a Birth Control Pill and Emptying of the Stomach in Women After Menopause (PHASE1)
• Selected Exercise Program on Upper Cross Syndrome Post-unilateral Mastectomy (NA)
• Therapies for Down Syndrome Regression Disorder (PHASE2)
• Opioid-Free Pain Protocol After Shoulder Arthroplasty (PHASE4)
• Opioid Use Post-Discharge After Ambulatory Distal Arm Surgery (NA)
• Opioid Analgesic Reduction Study (PHASE3)
• A Study to Evaluate Efficacy, Safety, and Tolerability of Alemtuzumab in Pediatric Patients With RRMS With Disease Activity on Prior DMT (PHASE3)

Primary sources

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