Battle of Honey Springs

Semorphone (Mr 2264) is an opiate analogue that is an N-substituted derivative of oxymorphone.

Semorphone is a partial agonist at μ-opioid receptors. It is around twice the potency of morphine, but with a ceiling effect on both analgesia and respiratory depression^[1] which means that these effects stop becoming any stronger after a certain maximum dose.

It is not currently used in medicine, and is not a controlled drug, although it might be considered to be a controlled substance analogue of oxymorphone on the grounds of its related chemical structure in some jurisdictions such as the United States, Canada, Australia and New Zealand.

References

^ Behne M, Bremerich D, Heinrich J, Schumacher H, Scherer M (1994). "Respiratory effects and tolerability of Mr 2264 Cl. A new opiate partial agonist in comparison with morphine and placebo". European Journal of Clinical Pharmacology. 46 (4): 301–4. doi:10.1007/BF00194395. PMID 7957512. S2CID 33001046.

[1] Behne M, Bremerich D, Heinrich J, Schumacher H, Scherer M (1994). "Respiratory effects and tolerability of Mr 2264 Cl. A new opiate partial agonist in comparison with morphine and placebo". European Journal of Clinical Pharmacology. 46 (4): 301–4. doi:10.1007/BF00194395. PMID 7957512. S2CID 33001046.

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