COVID-19 is an emerging, rapidly evolving situation.
Get the latest public health information from CDC:

Get the latest research information from NIH: Menu

N-acetylcysteine in the Treatment of PTSD and Addiction (NAC)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02499029
Recruitment Status : Completed
First Posted : July 15, 2015
Results First Posted : August 29, 2018
Last Update Posted : August 29, 2018
Information provided by (Responsible Party):
Medical University of South Carolina

Brief Summary:
Examine the effects of N-acetylcysteine on PTSD symptoms, craving and substance use in veterans with PTSD and comorbid substance use disorders.

Condition or disease Intervention/treatment Phase
PTSD Addiction Drug: N-acetylcysteine Drug: Placebo Phase 2

Detailed Description:
With the increased number of military veterans returning from conflicts in Afghanistan and Iraq diagnosed with posttraumatic stress disorder (PTSD), there is a high vulnerability of these individuals to develop a substance use disorder (SUD). While there have been a host of studies focused largely on dopaminergic mechanisms of drug reward, they have not led to the development of adequate treatments for either preventing people diagnosed with PTSD from developing SUD or for treating comorbid PTSD/SUD. Based on extensive work with addictive drugs and preliminary data from our group, the investigators propose that stress impairs prefrontal cortex regulation of the basal ganglia habit circuitry and this pathology renders PTSD patients susceptible to developing SUD. Moreover, the known effects of addictive drugs to further impair prefrontal regulation are synergistic with this pathology, thereby making treatment of comorbid PTSD/SUD particularly difficult. Preclinical studies have revealed that glutamate levels within the nucleus accumbens have been implicated in drug seeking behavior in the animal model of relapse. The amino acid precursor N-acetylcysteine (NAC) appears to restore glutamate to normal levels and may also prevent glutamate levels from spiking following subsequent stimulant use. The primary goal of the proposed study is to evaluate the efficacy and safety of N-acetylcysteine in preventing relapse in drug dependent individuals with PTSD or subthreshold PTSD. Veterans with substance use disorders who have achieved at lease one week of abstinence will be randomized to either placebo or NAC (2400-3600mg/day) for 8 weeks.

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 35 participants
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Glial Regulators for Treating Comorbid Posttraumatic Stress and Substance Abuse Disorders
Study Start Date : February 2013
Actual Primary Completion Date : September 2014
Actual Study Completion Date : September 2014

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: N-Acetylcysteine
Eligible participants were randomized to either NAC (2400 mg/day) or placebo for 8 weeks. The starting dose of NAC was 1200 mg twice daily (2400 mg/day). All NAC and placebo capsules contained riboflavin 25 mg, which was used as a biomarker for medication compliance.
Drug: N-acetylcysteine
NAC pills were administered each week. NAC is a N acetyl pro-drug of the naturally-occurring amino acid cystine. NAC is a white, crystalline powder with the molecular formula C5H9NO3S and with a molecular weight of 163.2.
Other Name: NAC

Placebo Comparator: Placebo
Identical appearing placebo capsules were dispensed. All NAC and placebo capsules contained riboflavin 25 mg, which was used as a biomarker for medication compliance. Study medications (USP-grade NAC and matched placebo capsules) dispensed to participants by the medical clinician or study staff. Treatment assignment followed a pre-arranged randomization scheme and was carried out by study personnel at the pharmacy (i.e., personnel not involved in clinical management of participants to preserve the double-blind design).
Drug: Placebo
Identical looking placebo pills were administered each week.

Primary Outcome Measures :
  1. PTSD Symptoms [ Time Frame: 8 weeks ]
    Clinician Administered PTSD Scale IV (CAPS) The CAPS IV measures seventeen symptoms based on intensity and frequency. Intensity and frequency scores are summed to create a severity score for each question. Severity scores are summed to get a total score. A higher total score indicates a higher severity of PTSD symptoms.The full range for CAPS IV is 0-136.

Secondary Outcome Measures :
  1. Depression [ Time Frame: 8 weeks ]
    Beck Depression Inventory (BDI) The BDI measures presence and severity of depression. It has 21 questions that are rated from 0-3 with a highest possible score of 63. A higher score indicates a higher severity of depression.

  2. Craving [ Time Frame: 8 weeks ]
    Visual Analogue Scale (VAS) The VAS measures alcohol craving on a scale from 0 to 10. A higher score indicates a higher level of craving.

  3. PTSD Symptoms [ Time Frame: 8 weeks ]
    PTSD Checklist - Military (PCL-M) The PCL-M is a seventeen question self-report, scored on a scale from 1 to 5, with possible scores ranging from 17 to 85. The scores from each question are summed to get a total score (17-85). A higher total indicates a higher severity of PTSD symptoms.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • 18-65 year old
  • U.S. military Veteran, Reservist, or National Guard member
  • DSM-IV diagnostic criteria for current (past 6 months) SUD and PTSD or subthreshold PTSD (i.e., met criteria for cluster B (re-experiencing) and either cluster C (avoidance) or D (hyperarousal), as well as duration of one month and clinically significant impairment)
  • Score of > 21 on the Mini-Mental State Exam (MMSE).

Exclusion Criteria:

  • Unstable medical conditions
  • Bipolar or psychotic disorders
  • Seizures or asthma
  • Prior treatment with NAC
  • Suicidality
  • Enrolled in ongoing PTSD treatment (pharmacotherapy or psychosocial)
  • Females: could not be pregnant or lactating
Publications of Results:
Layout table for additonal information
Responsible Party: Medical University of South Carolina Identifier: NCT02499029    
Other Study ID Numbers: Pro00021986
First Posted: July 15, 2015    Key Record Dates
Results First Posted: August 29, 2018
Last Update Posted: August 29, 2018
Last Verified: July 2018
Additional relevant MeSH terms:
Layout table for MeSH terms
Behavior, Addictive
Compulsive Behavior
Impulsive Behavior
Antiviral Agents
Anti-Infective Agents
Respiratory System Agents
Free Radical Scavengers
Molecular Mechanisms of Pharmacological Action
Protective Agents
Physiological Effects of Drugs