Analgesic is a collective term for any member of the diverse group of drugs used to relieve pain. Analgesic drugs include the nonsteroidal anti-inflammatory drugs (NSAIDs) such as the salicylates, narcotic drugs such as morphine, and synthetic drugs with narcotic properties.
NSAIDs such as aspirin, paracetamol (also called acetaminophen) and ibuprofen not only relieve pain but also reduce fever and inflammation. Narcotic analgesics and the morphine-like synthetic drugs depress the central nervous system and alter the perception of pain (Nociception). They are used to alleviate pain not relieved by the NSAIDs.
Analgesics are frequently used in combination, such as the paracetamol and codeine preparations found in many non-prescription pain relievers. They can also be found in combination with vasodilation drugs such as Pseudoephidrine for sinus-related preparations, or with anti-histamine drugs for allergy sufferers.