This investigation will be the first study assessing genetic modulation of naltrexone's NTX effects upon the abuse liability of a stimulant drug (methamphetamine). The study team will assess the ability of oral NTX to block the reinforcing and positive subjective effects of intranasal (IN) methamphetamine (30mg/70kg). This investigation could identify an important Gene x Pharmacological interaction, contributing to the personalization of stimulant abuse pharmacotherapy.
Name: Intranasal Methamphetamine
Description: To assess the reinforcing effects of methamphetamine, participants complete a drug vs. money self-administration procedure. The outcome measure for this procedure is their percentage of choices for drug (methamphetamine) choices.Measure: Percentage of methamphetamine choices. Time: 1 day.
Description: Participant ratings of methamphetamine "Liking," on a 100 mm visual analog scale. Participants are asked to indicate on a 100 mm line the extent to which they agree with the description of the drug provided. The 0 mm end of the line indicates "Not at All," while the 100 mm indicates "Extremely."Measure: Positive subjective effects of methamphetamine. Time: 1 day
There is one SNP
Substance Use Disorders Methamphetamine Abuse Substance-Related Disorders A recent meta-analysis concluded that the OPRM1 A118G SNP (rs1799971) significantly moderates the treatment efficacy of Naltrexone (NTX) in treating alcohol abuse, increasing the treatment efficacy by over 2-fold among G-allele carriers (AG/GG). --- A118G ---
Medication effects on these validated predictors of abuse potential will be compared between A118G A allele homozygotes (AA) and G-allele carriers (AG/GG; an anticipated 25% of the total sample), in order to assess genetic moderation of treatment outcome. --- A118G ---