The post mortem findings of pentazocine and tripelennamine ("T's and Blues") in abusers dying in the City of St. Louis between July 1, 1979 and July 30, 1981 are presented. Thirty-three deaths were homicides; 30 black males, ages 21-38; one white male, age 26, died from gunshot wounds; and two black females, age 18 and 32, died of stab wounds. Blood concentrations of pentazocine and tripelennamine in these cases ranged from 0.20 to 3.3 mg/L, (mean +/- SD 0.72 +/- 0.64 mg/L) and 0.02 to 1.8 mg/L (mean +/- SD 0.29 +/- 0.40 mg/L), respectively. The six deaths attributed to T's and Blues abuse involved three black males, ages 20, 28 and 49, and three black females, ages 21, 25, and 45 years. Blood concentrations of pentazocine and tripelennamine ranged from 0.44 to 2.5 mg/L and 0.09 to 4.1 mg/L, respectively. Ethanol and diazepam were also detected in 49% and 13% of all deaths, respectively. Foreign body or talc granulomas in lung were the most common pathological finding relevant to the abuse of T's and Blues.