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How does oxycodone differ from hydrocodone? How powerful is fentanyl compared to morphine? A working knowledge of opioids is important for clinicians who treat patients with chronic pain. Opioids include:

  • Morphine, derived from secretions of the poppy plant. The strength of other opioids is usually given as “morphine equivalents,” based on equal weights.
  • Codeine, chemically modified from morphine. Codeine is about one-sixth as strong as morphine.
  • Heroin is derived from morphine. It is 5 times as strong as morphine, and has no approved human use.
  • Hydrocodone is derived from codeine. It is about as strong as morphine.
  • Hydromorphone is derived from morphine. It is 4 times as strong as morphine.
  • Oxycodone is derived from codeine. It is 1.5 times as strong as morphine.
  • Oxymorphone is derived from morphine. It is 3 times as strong as morphine.
  • Fentanyl is a synthetic opioid. It is about 100 times as strong as morphine. Because of the potential for overdose from oral medication, it is delivered with a transdermal patch.
  • Carfentanil is 10,000 times as strong as morphine, and has no approved human use.

An online dose equivalent calculator can be used to determine equivalent analgesic effects for different opioids. 

Published date: Dec. 17, 2018