[citation needed] Relative to morphine, levorphanol lacks complete cross-tolerance[8] and possesses greater intrinsic activity at the MOR.

[9] Levorphanol's exceptionally high analgesic efficacy in the treatment of neuropathic pain is also conferred by its action on serotonin and norepinephrine transporters, similar to the opioids tramadol and tapentadol, and mutually complements the analgesic effect of its NMDA receptor antagonism.

[10] Levorphanol shows a high rate of psychotomimetic side effects such as hallucinations and delirium, which have been attributed to its binding to and activation of the KOR.

The "right-handed" (dextrorotatory) enantiomer of racemorphan is dextrorphan (DXO), an antitussive, potent dissociative hallucinogen (NMDA receptor antagonist), and weakly active opioid.

In the U.S., it is a Schedule II Narcotic controlled substance with a DEA ACSCN of 9220 and 2013 annual aggregate manufacturing quota of 4.5 kilograms.