Analgesic

An analgesic, or painkiller, is any member of the group of drugs used to achieve analgesia.

The word analgesic derives from Greek ἀν-, “without”, and ἄλγος, “pain”.

Three types of pain medication

1. Nonopioid analgesic

a) Nonsteroidal anti-inflammatory drug: aspirin, ibuprofen, acetaminophen

2. Opioids

a) agonists

b) partial agonists

c) mixed agonists/antagonists.

3. drugs that are not strictly analgesics, but which act as adjuvants when added to any of the above: tricyclic antidepressants, anticonvulsants, caffeine, hydroxyzine, corticosteroids.

Opiates and acetaminophen are preferred analgesic agents, and gabapentin is a contextual third choice, in neurocritically ill patients. Other agents are rarely prescribed. The discordance in physician self-reports and objective audits suggest that pain management optimization studies are warranted. ¹⁾.

Analgesic drugs act in various ways on the peripheral and central nervous systems. They are distinct from anesthetics, which reversibly eliminate sensation, and include paracetamol (known in the US as acetaminophen or simply APAP), the Nonsteroidal anti-inflammatory drugs (NSAIDs) such as the salicylates, and opioid drugs such as morphine and oxycodone.

In choosing analgesics, the severity and response to other medication determines the choice of agent; the World Health Organization (WHO) pain ladder specifies mild analgesics as its first step.

Analgesic choice is also determined by the type of pain: For neuropathic pain, traditional analgesics are less effective, and there is often benefit from classes of drugs that are not normally considered analgesics, such as tricyclic antidepressants and anticonvulsants.