How do NSAIDs work and what are their common side effects?

Nonsteroidal anti-inflammatory drugs, or NSAIDs, work by inhibiting cyclooxygenase enzymes COX-1 and COX-2, reducing the production of prostaglandins that mediate pain, inflammation, and fever. Common NSAIDs include ibuprofen, naproxen, diclofenac, and ketorolac. Side effects include gastrointestinal irritation, ulceration, and bleeding because COX-1 prostaglandins normally protect the stomach lining. NSAIDs also increase cardiovascular risk, impair renal blood flow, and can worsen hypertension and heart failure.