|Common names||Ethylmorphine, codethyline, dionine|
|Systematic name||7,8-didehydro-4,5-α-epoxy- 3-ethoxy-17-methylmorphinan-6-α-ol|
ethylmorphine, also known as codethyline and dionine, is a semi-synthetic morphinan opioid first created by merck in 1884 and used as a weaker alternative to morphine. today, it is most commonly used as an antitussive which is available in cough syrup preparations like cocillana, cosylan, solvipect comp. (in combination with guaifenesin) and lepheton (in combination with ephedrine), or in tablet form sold as tussipax (in combination with codeine). cough syrup preparations commonly include a mild laxative to counter the constipation which is a common side effect of opioids.
ethylmorphine is also used in ophthalmic preparations as dionine to treat inflammations of the eye. in 1904, an ethylmorphine preparation was described as “a new ocular analgesic.”
ethylmorphine, or 3-ethylmorphine, is an opioid of the morphinan class. ethylmorphine and other molecules of this class contain a polycyclic core of three benzene rings fused in a zig-zag pattern called phenanthrene. a fourth nitrogen containing ring is fused to the phenanthrene at r9 and r13 with the nitrogen member looking at r17 of the combined structure. this structure is called morphinan.
ethylmorphine, along with other morphinans, contains an ether bridge between two of its rings, connecting r4 and r5 through an oxygen group. it contains a hydroxy group (oh-) bound at r6 and a methyl group located on the nitrogen atom at r17. on the same ring containing the hydroxy group, ethylmorphine contains a double bond which is shared with codeine and morphine.
ethylmorphine is closely related to morphine; both contain an oxygen group at r3, but this oxygen group in ethylphenidate is substituted by an ethyl group (making an ethoxy group). ethylmorphine differs from the naturally occurring codeine (3-methylmorphine) only in having an ethoxy group in place of the methoxy group (they are homologous). it is also analogous to the other morphinans such as dihydrocodeine, heroin, hydrocodone, and oxycodone.
the active metabolites of ethylmorphine, notably morphine, exert their effects by binding to and activating the μ-opioid receptor. this occurs because opioids structurally mimic endogenous endorphins which are naturally found within the body and also work upon the μ-opioid receptor set. the way in which opioids structurally mimic these natural endorphins results in their euphoria, pain relief and anxiolytic effects. this is because endorphins are responsible for reducing pain, causing sleepiness, and feelings of pleasure. they can be released in response to pain, strenuous exercise, orgasm, or general excitement.
ethylmorphine has been described as less potent than morphine but slightly more potent than codeine.