Narcotic Analgesics

Narcotics and Opioids

Narcotic analgesics include two types, opiates and derivatives of opiates, the opioids. Opiates are the natural opium alkaloids and the opioid derivatives are the synthetic compounds.

These types of analgesics are further classified as agonists or agonist/antagonist. Such agents as morphine, codeine, hydromorphone, levorphanol, meperidine, methadone, and propoxyphene are agonists. They bind to central nervous system opiate receptors to produce analgesia. By binding to the CNS receptor sites, the perception of pain is reduced.

Agents buprenorphine, butorphanol, nalbuphine and pentazocine are both agonist/antagonists. They also bind to central nervous system receptors. These drugs act as antagonist when other narcotics are used. They block their effect causing withdrawal symptoms.

Narcotic analgesics are used in moderate to severe types of pain.

These drugs can produce side effects such as respiratory depression, therefore caution should be used when giving these drugs in those that have respiratory compromise.

They are metabolized in the liver and excreted through the kidneys. Additional cautionary measures should be used in those with hepatic or renal impairment.

See individual drugs for further information.