Quinine Concentrations in Blood Following the Consumption of Gin and Tonic Preparations in a Social Setting

Abstract

In some parts of the country, quinine is often detected in heroin users as the result of its use to dilute the narcotic. It is also used in various medical preparations and in some beverages. In order to evaluate quinine concentrations in blood after ingestion of quinine-containing beverages under the conditions of “social drinking,” mixtures of gin and tonic (quinine) water were imbibed by human subjects in a social setting. Blood samples were taken at 45-minute intervals for quinine analysis and urine samples were collected at 12 and 24 hours in some subjects. The mean concentration found was 0.22 ± 0.01 µg/ml after three drinks. This was substantially lower than concentrations reported after therapeutic administration, or after death from quinine-containing narcotics.