Pain medications are drugs used to relieve discomfort associated with disease, injury, or surgery. Because the pain process is complex, there are many types and drug classifications of pain drugs that provide relief by acting through a variety of physiological mechanisms. Thus, effective medication for nerve pain will likely have a different mechanism of action than arthritis pain medication.

• Nonsteroidal anti-inflammatory drugs (NSAIDs) act on substances in the body that can cause inflammation, pain, and fever.
• Corticosteroids are often administered as an injection at the site of musculoskeletal injuries. They exert powerful anti-inflammatory effects. They can also be taken orally to relieve pain from, for example, arthritis.
• Acetaminophen increases the body’s pain threshold, but it has little effect on inflammation.
• Opioids, also known as narcotic analgesics, modify pain messages in the brain.
• Muscle relaxants reduce pain from tense muscle groups, most likely through sedative action in the central nervous system.
• Anti-anxiety drugs work on pain in three ways: they reduce anxiety, they relax muscles, and they help patients cope with discomfort.
• Some antidepressants, particularly tricyclics, may reduce pain transmission through the spinal cord.
• Some anticonvulsant drugs also relieve the pain of neuropathies, possibly by stabilizing nerve cells.