What analgesics can be given to a patient allergic to codeine?
For a patient with a true allergy to codeine, the risk of cross-reactivity with another opioid can be reduced if an analgesic from a different chemical class is used. Chemically, there are three classes of opioid analgesics: phenanthrenes, phenylpiperidine, and phenylheptanones. Morphine and its related opioids, including codeine, are in the phenanthrene class. The mixed agonist-antagonist agents (buprenorphine, nalbuphine, butorphanol, pentazocine, and dezocine) are also included in the phenanthrenes. Use of any of these agents in a patient with a true allergy to codeine may result in an allergic reaction. Meperidine and its related congeners are phenylpiperidines, while methadone and propoxyphene are phenylheptanones. Selecting agents from a different chemical class should minimize the risk of cross-sensitivity. However, it is important to note that use of an opioid from a different chemical class does not eliminate the risk of an allergic reaction. For patients with severe or life-t
