Alcohol tolerance in patients with non-insulin-dependent (type 2) diabetes treated with sulphonylurea derivatives

The oral ethanol loading test (0.5 g/kg body mass given as 40% solution) was carried out in 5 groups, each of 10 out-patients with non-insulin-dependent (type 2) diabetes before and after 10 days of treatment with one of the following sulphonylurea derivatives: tolbutamide (CAS 64-77-7) 0.5 t.i.d., chlorpropamide (CAS 94-20-2) 0.5 once daily morning, glibornuride (CAS 26944-48-9) 0.025 t.i.d., glibenclamide (CAS 10238-21-8) 0.005 t.i.d. and glipizide (CAS 29094-61-9) 0.005 t.i.d. The response to alcohol (facial flush, heart rate, blood pressure) were compared, and blood concentrations of ethanol, acetaldehyde, pyruvate, lactate, hydrocarbonates as well as blood pH, pO2 and pCO2 were determined in fasting state and during 6 hours after alcohol ingestion. In all patients the family history of diabetes and the presence and degree of vascular complications were registered. Evident flushing phenomenon was observed in 6 patients treated with chlorpropamide, in 3 treated with tolbutamide, in 2 treated with glibenclamide, in one receiving glibornuride and in none treated with glipizide. All drugs caused a greater rise of blood ethanol and acetaldehyde levels in relation to the control tests, but the difference reached statistical significance only in the group receiving chlorpropamide. Moreover, patients (pooled) with positive thermographic response had also significantly higher blood levels of ethanol and acetaldehyde during the second test. The ratio of acetaldehyde to ethanol concentration in blood (mumol:mmol) was not significantly changed in any group indicating parallel impairment of both steps of ethanol metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)