Dihydroisocodeine is an

opioid Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioi ...

. The National Research Council of the United States reported in 1941 that isocodeine is one of four isomers of

codeine Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, ''Papaver somniferum''. It is typically use ...

known at the time ( heterocodeine can be considered a fifth) and DHIC, then in use in Europe as a pharmaceutical, was four times stronger than dihydrocodeine as isocodeine is four times stronger than codeine. The other isomers of codeine are allocodeine and pseudocodeine and they are active drugs as is heterocodeine, which is estimated to be up to 108 times as potent as codeine. Report of the Committee On Drug Addiction 1929-1941 With Monographs; National Research Council (US) New York, Washington, Philadelphia 1941, 1116 pages

References

Opioids {{analgesic-stub