Table 1.

Demographic and drug use characteristics.

Participant characteristics	Placebo (N = 16)	Riv 3 mg (N = 13)	Riv 6 mg (N = 12)
Demographics
Females (%)	12.5	23.1	16.7
Caucasian (%)	0	7.7	16.7
African–American (%)	68.8	69.2	75.0
Hispanic (%)	12.5	23.1	8.3
Mixed	18.8	0	0
Age (years)	40.4 ± 2.0	43.9 ± 1.6	43.5 ± 1.6
Education (years)	12.1 ± 0.3	12.7 ± 0.5	13.3 ± 0.6
Estimated premorbid IQ	96.5 ± 3.8	98.8 ± 3.4	102.9 ± 3.0
Cocaine use
Route of use-smoke (%)	100	100	91.7
Use in last 30 (days)	16.2 ± 1.9	18.6 ± 1.6	18.7 ± 2.7
Use lifetime (years)	15.6 ± 1.8	15.8 ± 2.4	15.8 ± 2.3
Grams per day	1.7 ± 0.3	2.9 ± 1.0	2.1 ± 0.4
Nicotine use	N = 14	N = 11	N = 10
Use in last 30 (days)	22.2 ± 2.6	21.2 ± 2.0	30.0 ± 0.0
Use lifetime (years)	17.4 ± 2.1	19.8 ± 2.2	21.8 ± 3.2
Cigarettes per day	9.3 ± 1.7	7.9 ± 1.6	14.3 ± 1.7*
Alcohol use	N = 15	N = 9	N = 10
Use in last 30 (days)	9.5 ± 2.1	10.8 ± 2.3	11.3 ± 3.0
Use lifetime (years)	19.1 ± 2.2	23.8 ± 0.8	19.1 ± 2.6
Drinks per day	3.1 ± 0.6	2.8 ± 0.4	2.4 ± 0.4

Values represent Mean ± SEM.

Number represents current users only.

Number represents days used in the part 30.

Number represents total number of years substance was used.