Possible Interaction: Ethanol and Codeine

“The presence of other central nervous system (CNS) depressants (i.e. benzodiazepines, hypnotics, and/or alcohol ) was significantly associated with lower codeine concentration as compared to CRD in which other CNS depressants were not detected (p=0.0002).”

“A suggestion is made that a closer examination be undertaken of the involvement in road crashes of the more widely available narcotic drugs codeine and propoxyphene when they are taken together with alcohol.”

“In conclusion ethanol co-incubation with codeine resulted in an inhibition of codeine conversion to unknown metabolites and norcodeine, and with morphine to morphine-3-glucuronide, but no inhibition in morphine production.”

“In the presence of ethanol the concentrations of several intermediate and end products of ethylmorphine and codeine changed markedly from the control situation.”

“It was concluded that all steps in the metabolism of ethylmorphine (and codeine ) leading to the end products morphine-3-glucuronide and normorphine-3-glucuronide were inhibited by ethanol , and that the glucuronidation process were the ones most affected by ethanol.”

“The elimination rate constant (Kel) of codeine and morphine was reduced with approximately one-third and one-fourth, respectively, in the presence of 60 mM ethanol , whereas the presence of ethanol did not alter the Kel of norcodeine significantly.”

“The inhibition of codeine metabolism was dose-dependent, extending from approximately 15% at 10 mM ethanol to … 50% at 100 mM. A 3-fold increase in the ratio of morphine concentration (formed from codeine ) to the amount of codeine … observed in the presence of ethanol as compared … control cells.”