Experimental: Treatment

Cognitive-behavioral counseling for marijuana and smoking cessation, mobile contingency management for marijuana and smoking cessation, transdermal nicotine patch (7-21 mg over six weeks), nicotine polacrilex or nicotine lozenge (4 mg administered as needed over six weeks), bupropion (150 mg once per day for 7 days, then 150 mg twice per day for about six months.

Drug: bupropion

Prescribed one week prior to quit and continued until the 6 month follow-up visit.

Other Name: Zyban

Drug: transdermal nicotine patch

Initiated at smoking quit date; 7 mg to 21 mg patch depending on amount smoked by participant

Drug: Nicotine polacrilex

Initiated at smoking quit date.

Other Name: nicotine gum; nicorette

Drug: nicotine lozenge

Initiated at smoking quit date.

Behavioral: counseling for marijuana and smoking cessation

5 sessions of cognitive-behavioral counseling designed to facilitate marijuana and smoking cessation and promote relapse prevention

Behavioral: mobile contingency management

treatment that provides money rewards for abstinence from smoking and marijuana