DOX as a Potential Treatment for Methamphetamine Dependence
Condition: Substance-Related Disorders
MeSH terms: Substance-Related Disorders
Study type: Interventional
Phase: Phase 1

Summary: 
      The purpose of the study is to asses the potential interactions between methamphetamine and
      doxazosin in methamphetamine-dependent volunteers who are not seeking treatment. The study
      will evaluate the effects of doxazosin on the cardiovascular and subjective effects of
      methamphetamine in a human laboratory study.

      The primary objective is to determine the safety of treatment with doxazosin in
      methamphetamine-dependent volunteers by examining hemodynamic and subjective effects of
      administration of ascending doses of methamphetamine and a placebo dose during treatment with
      doxazosin.

      The secondary objective is to determine effects of treatment with doxazosin, as compared to
      placebo, on subjective effects produced by administration of methamphetamine or placebo
    

Detailed description: 
      Purpose:

      To determine the effects of treatment with doxazosin, compared to treatment with placebo, on
      methamphetamine-induced craving and subjective effects in methamphetamine-dependent human
      volunteers.

      Secondary aims are to clarify the genetics of substance abuse, potentially leading to
      improved methods to diagnosis those at risk and to help develop better therapeutic
      interventions and to develop a new saliva-based test for the detection and measurement of
      drugs of abuse.

      Design/Procedure:

      Twenty non-treatment-seeking methamphetamine-dependent volunteers will complete procedures
      during treatment with placebo and study medication, in random order, using a within-subjects,
      double-blind, placebo-controlled design. There will be a two week period between each phase.
      The dose of doxazosin needed to alter the effects of methamphetamine is unknown and
      preclinical animal studies have not been conducted. Because of this, initially the
      investigators will study the effects of a low dose of doxazosin (4mg daily) compared to
      placebo daily. Methamphetamine (0, 10, and 30mg, smoked) will be administered during
      treatment with 4mg doxazosin/placebo. Methamphetamine will be administered in ascending dose
      (10mg followed by 20mg) with the 0mg dose randomly interspersed to maintain the blind.
      Cardiovascular measures and subjective effects ratings will be assessed following
      methamphetamine administration.

      Participants will be monitored for stability on days 11 and 12 and discharged from the
      hospital on day 13.

      If 4mg doxazosin treatment is well tolerated but is not associated with alterations in the
      effects of methamphetamine, a second group of subjects will be studied using the same sample
      size. Treatment will begin at 1mg and increased by 1mg increments every three days until 8mg
      is reached. Placebo will be dosed identically. All study procedures will be identical as
      described above.
    

Intervention name(s): Sugar Pill; Doxazosin
Intervention type(s): Drug; Drug
Intervention description(s): The administration of a sugar pill; The administration of the Doxazosin medication
Intervention MeSH terms: Doxazosin
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Care Provider)
Keywords: Methamphetamine; Dependence