Providing straightforward information pertaining to drugs, drug use & drug policy. The Grey Pages promotes drug-related literacy and advocates a system of viable and tolerant drug policies. This is my personal collection of commentaries, essays, tid-bits, and other such writings on everything ranging from drug use, drug policy and drug-myths, to drug-science, addiction, human behavior, and the workings of the human brain. I started this blog with a particular focus on opioids, and over the past year have found my interest gravitate toward the intriguing, ever-changing world of designer intoxicants (i.e. "research chemicals" or "designer drugs").

Sunday, October 30, 2011

Racemorphan: Evidence Based Overview

Who else would love to try this? I wonder what type of rush it would give when injected via IV route...

Synthetic opioid of the morphinan type. Chiral mixture of both levorphanol and dextrorphanol. Also referred to as morphanol.

Multiple modes of action as a narcotic mu agonist, NMDA antagonist, sigma agonist, and a serotonin & norepinephrine reuptake inhibitor.

Roughly half as potent as levorphanol, or about 2 - 2.5x as potent as morphine. 4-5mg intravenously is equianalgesic to 2mg levorphanol and 10mg morphine (IV route). 8 - 10mg orally is comparable to 30mg morphine.

Can be (and has been) given by almost any route: oral, rectal, SC, IM, IV.

Very effective pain reliever. May be superior to morphine in cancer and neuropathic pain. Single doses of 5mg parenterally (IV or IM) have generally speaking, been effective for almost any type of pain - to include cancer and post-operative pain. Suppression of severe cough can be achieved with 2 - 4mg subcutaneously.

Longer acting than morphine with effects which range 6 - 12 hours, depending on dosage and ROA. Even parenteral doses have provided effects for up to 12 hours, or up to 18 hours post operatively when given intravenously as a supplement to nitrous oxide anaesthesia.

Has been observed to have strong sedative tendencies in some cases, due in part to NMDA blocking activity.

Side effect profile is similar to morphine. No significant difference in respiratory depression. May cause less itching and constipation than morphine.

Tolerance development is slower than that of morphine in most cases - comparable with levorphanol, methadone, or other long acting, NMDA active opioids.

Substitutes completely in morphine addicts and fully suppresses morphine abstinence symptoms. Dependence potential is high.

Subjective effects are similar to those of other mu agonists. Injections in post-morphine addicts produced morphine-like euphoria, sedation, relaxation, and requests for more of the drug. One author reported 7.5mg racemorphan produced subjective effects comparable to 30mg morphine, both parenterally. Euphoria is most pronounced by the IV route, onset is slightly delayed compared with morphine.


  1. I'd like to try that, sounds good to me.

  2. It really does. Something about obscure/unavailable opioids which makes me really want to try them. I imagine it's similar to the racemic mixture of methadone used in the US.