Complementary Combination Therapy for Cocaine Dependence

Participants will be randomized into two groups: placebo and doxazosin 8 mg/d. The doxazosin dose will be increased every 4 days over 11 days, starting with 1mg on the first study day and and ending with 8mg 11 days later. Participants will receive one capsule daily that will contain either placebo or doxazosin.

After titrating doxazosin to the target dose, study procedures will be completed three times, once during treatment with each dose of modafinil (0 \[placebo\], 200, and 300 mg/d), in pseudo-random order such that 200 mg precedes 300 mg).

On the 5th day of study medication treatment participants will receive non-contingent doses of cocaine (placebo, 20, 40 mg, IV) and participate in cocaine self-administration sessions.