RT Journal Article
SR Electronic
T1 A Method to Quantify Illicit Intake of Drugs from Urine - Methamphetamine
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP jpet.111.179176
DO 10.1124/jpet.111.179176
A1 Linghui Li
A1 Gantt P Galloway
A1 Davide Verotta
A1 Thomas E Everhart
A1 Matthew J Baggott
A1 Jeremy R Coyle
A1 Juan C Lopez
A1 John Mendelson
YR 2011
UL http://jpet.aspetjournals.org/content/early/2011/03/30/jpet.111.179176.abstract
AB Qualitative urinalysis can verify abstinence of drug misuse but cannot detect changes in drug intake. For drugs with slow elimination, like methamphetamine (MA), a single episode of abuse can result in up to 5 days of positive urine drug screens. Thus, interventions that produce substantial decreases in drug use but do not achieve almost complete abstinence are classified as ineffective. Using non-pharmacologic doses of deuterium-labeled l-methamphetamine (l-MA-d3) we have developed a simple, robust method that reliably estimates changes in MA intake. Twelve subjects were dosed with 5 mg l-MA-d3 daily and challenged with 15, 30 and 45 mg of non-labeled d-MA (d-MA-d0) after reaching plasma steady status of l-MA-d3. Urinary concentration ratios of d-MA-d0 to l-MA-d3 provided clear separation of the administered doses with as little as 15 mg dose increments. Administered doses could not be resolved using d-MA-d0 concentrations alone. In conclusion, the urinary [d-MA-d0 ] : [l-MA-d3] provides a quantitative, continuous measure of illicit MA exposure. The method reliably detects small, clinically relevant changes in illicit MA intake from random urine specimens, is amenable to deployment in clinical trials, and can be used to quantify patterns of MA abuse.