N-Acetylcysteine and Smoking Reduction

A Randomized Controlled Trial of Oral N-acetylcysteine for Smoking Reduction: a Pilot Study

N-acetylcysteine is an inexpensive agent with a benign side effect profile with preliminary studies in humans suggesting efficacy for the treatment of cocaine dependence. N-acetylcysteine has been used in clinical medicine for nearly three decades to treat chronic lung conditions, acetaminophen overdose, and experimentally to treat cocaine dependence. It is generally safe and well tolerated. The present pilot study seeks to explore safety and tolerability, ad lib smoking, visual cue reactivity, and smoking reduction rates in a group of nontreatment seeking, nicotine dependence smokers who are willing to undergo a brief trial with oral N-acetylcysteine 1200 mg twice daily.

Study Overview

• Status: Completed
• Conditions: Nicotine Dependence
• Intervention / Treatment: Drug: N-acetylcysteine; Drug: Placebo

• Study Type: Interventional
• Enrollment (Actual): 33
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • South Carolina
    • Charleston, South Carolina, United States, 29425
      • Medical University of South Carolina

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Be smokers motivated to reduce their cigarette usage but not seeking treatment to quit smoking at the time of screening.
2. Be Able to give written informed consent after being presented with an IRB-approved informed consent document
3. Be male or female of any race, between eighteen and sixty five years of age.
4. Be in stable physical and mental health as judged by interview
5. Be smoking 10 or more cigarettes per day for one or more years
6. Have an expired CO reading of ≥10 parts/million prior to beginning study
7. Test non-pregnant and use adequate birth control (female only). All female subjects will have a urine pregnancy test performed prior to the first dose of study medication.
8. Be able to comply with protocol requirements and be likely to complete all study treatments.
9. Live within 50 miles of the study site

Exclusion Criteria:

1. Have current dependence, defined by DSM IV criteria, on any psychoactive substance other than nicotine, alcohol, or marijuana or physiological dependence on alcohol requiring medical detoxification.
2. Have a history of significant hepatic, renal, endocrine, cardiac (i.e., arrhythmia requiring medication, angina pectoris, myocardial infarction,), stroke, seizure, neurological, non-drug-related psychiatric, gastrointestinal, pulmonary, hematologic or metabolic disorders.
3. Have a history of adverse reaction/hypersensitivity to N-acetylcysteine.
4. Have any significant active medical or psychiatric illness (e.g. schizophrenia, suicidal/homicidal ideation within the past 30 days) which might inhibit their ability to complete the study or might be complicated by administration of NAC.
5. Used carbamazepine or Nitroglycerin within the last 14 days or any other medication felt to be hazardous if taken with NAC
6. Have a current or past history of asthma and/or the occasional or daily use of Albuterol or other beta-agonist inhalers.
7. Females pregnant or breast-feeding
8. Have any medical history or condition considered by the investigator(s) to place the subjects at increased risk.
9. Not fail to actively meet the inclusion criteria at the time of screening.
10. Have a history of childhood or adult seizures of any cause.
11. Be currently taking any medications (i.e., beta-blockers, stimulant medications) that might affect heart rate or skin conductance

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 1; 2400mg N-acetylcysteine (1200mg b.i.d.) for 4 consecutive weeks	Drug: N-acetylcysteine; 2400mg (1200mg b.i.d., 600mg capsules, p.o.)
Placebo Comparator: 2; Identically appearing placebo pills, packaged in an N-acetylcysteine "slurry" so that placebo will retain smell similar to active NAC capsules	Drug: Placebo; Identically appearing placebo capsules, packaged in an N-acetylcysteine "slurry" so that placebo has similar odor as active NAC capsules

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Carbon Monoxide Levels	Weekly
Smoking Level	Weekly
Craving Levels (Questionnaire for Smoking Urges -- Brief)	Weekly
Minnesota Nicotine Withdrawal Scale (MNWS)	Weekly

Secondary Outcome Measures

Outcome Measure	Time Frame
Smoking Level	Daily

Collaborators and Investigators

• Sponsor: Medical University of South Carolina
• Collaborators: National Institute on Drug Abuse (NIDA)
• Investigators: Principal Investigator: Steven LaRowe, PhD, Medical University of South Carolina

Study record dates

Study Major Dates

• Study Start: December 1, 2006
• Primary Completion (Actual): October 1, 2007
• Study Completion (Actual): October 1, 2007

Study Registration Dates

• First Submitted: September 10, 2008
• First Submitted That Met QC Criteria: September 10, 2008
• First Posted (Estimate): September 11, 2008

Study Record Updates

• Last Update Posted (Actual): March 23, 2017
• Last Update Submitted That Met QC Criteria: March 22, 2017
• Last Verified: September 1, 2008

More Information

Terms related to this study

• Keywords: Nicotine; smoking reduction; N-acetylcysteine
• Additional Relevant MeSH Terms: Mental Disorders; Chemically-Induced Disorders; Substance-Related Disorders; Tobacco Use Disorder; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Anti-Infective Agents; Antiviral Agents; Protective Agents; Respiratory System Agents; Antioxidants; Antidotes; Free Radical Scavengers; Expectorants; Acetylcysteine; N-monoacetylcystine
• Other Study ID Numbers: P50DA015369 (U.S. NIH Grant/Contract)