Conditions: Nicotine Dependence Nicotine Withdrawal
Keywords: Tobacco Nicotine Smoking Varenicline Bupropion Human laboratory study Stress tolerance Startle response Cognitive assessment Progressive ratio Motivation
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 121
Healthy volunteers: yes

Brief summary:
The objective of this proposal is to elucidate effects of bupropion SR + varenicline on smoking-cessation related processes in early abstinence using a human laboratory model. A within-subjects design will be used to assess the additive effects of bupropion and varenicline in 48 treatment seeking smokers \[bupropion SR (300 mg/day)+placebo, varenicline (2 mg/day+placebo, and bupropion SR (300 mg/day)+varenicline (2 mg/day)\]. Outcomes include withdrawal and craving, cognition, stress tolerance, anxiety, the reinforcing effects of smoking, and smoking topography.

Hypotheses: We hypothesize that greatest treatment effects will be observed in the bupropion SR+varenicline group followed by varenicline+placebo and bupropion SR+placebo groups.

Detailed description:

Arms:
arm 1: Bupropion + Placebo Varenicline \\Varenicline + Placebo Bupropion; Varenicline + Placebo Bupropion \\Bupropion + Placebo Varenicline arm 2: Bupropion + Varenicline \\Varenicline + Placebo Bupropion; Varenicline + Placebo Bupropion \\Bupropion + Varenicline

Interventions: intervention 1: Bupropion intervention 2: Varenicline
Intervention descriptions: intervention 1: Form: tablet, Dosage, Frequency, Duration: Days 1-3, 150 mg, q.d., Days 4-11, 150 mg, b.i.d. intervention 2: Form: tablet, Dosage, Frequency, Duration: Days 1-3, .5 mg, q.d., Days 4-7, .5 mg, b.i.d., Days 8-11, 1 mg, b.i.d.

Protocol document: