Ibuprofen

Adults: 200–400 mg every 4–6 hours, max 1200 mg per day without medical advice.

Stomach upset, heartburn, nausea. Long-term use may increase risk of ulcers, kidney problems, and cardiovascular events.

Active stomach ulcer, severe kidney or heart failure, third trimester of pregnancy.

Ibuprofen inhibits cyclooxygenase enzymes, reducing the prostaglandins that drive pain and swelling. Commonly used for headache, dysmenorrhea, back pain, arthritis, and minor injuries.