D-Cycloserine Enhancement of Exposure-Based CBT for Smoking Cessation (DCSSmoking)

In comparison to placebo-augmented cognitive behavioral therapy (CBT),
D-cycloserine-augmented CBT will lead to a greater reduction in both short-and long-term
point prevalence abstinence as well as time to first smoking lapse and time to smoking
relapse.

Inclusion Criteria:

1. Be a regular smoker for at least one year 3. Currently smoke an average of at least 10
cigarettes per day 4. Report a motivation to quit smoking in the next month of at least 5
on a 10 point scale 5. Score 20 or greater on the 16-item Anxiety Sensitivity Index
(Schmidt & Joiner, 2002).

Exclusion Criteria:

1. Current diagnosis of a psychotic, eating, developmental or bipolar disorder (as
determined by the SCID)

2. Current anxiety or mood disorder rated moderate or greater (i.e., CGI score of 4 or
greater for an anxiety or depressive disorder or any current or recent—1
year--suicidal ideation)

3. Psychoactive substance abuse or dependence (excluding nicotine dependence) within the
past 6 months

4. Current use of isoniazid psychotropic medication

5. A history of significant medical condition, such as cardiovascular, neurologic,
gastrointestinal, pregnancy and/or breast feeding, history of seizure (other than
febrile seizures in childhood) or other systemic illness and/or be deemed as
currently unhealthy in the context of a complete physical examination

6. Limited mental competency and the inability to give informed, voluntary, written
consent to participate,

7. Current use of any pharmacotherapy or psychotherapy for smoking cessation not
provided by the researchers during the quit attempt,

8. Concurrent psychotherapy initiated within three months of baseline, or ongoing
psychotherapy of any duration directed specifically toward treatment of anxiety or
mood disorder other than general supportive therapy initiated at least 3 months prior
to the study

9. Use of other tobacco products

10. Planning on moving (outside of the immediate area) in the next six months

11. Insufficient command of the English language (i.e., they cannot carry on a
conversation with an interviewer in the English language or read associated text).