Drug use frequency among street-recruited heroin and cocaine users in Harlem and the Bronx before and after September 11, 2001.

We determined if illicit drug use frequency changes after a disaster by comparing drug use frequency in two street-recruited samples of heroin and cocaine users, ages 15-40 years. The users were interviewed between July 11 and November 11 and divided into before- and after-September 11th groups for analysis. The before and after groups were similar in the mean number of days of drug use per month (sniff cocaine 6.8 days vs. 9.4 days, respectively, P =.17; snorted heroin 13.9 vs. 14.0, respectively, P =.96; smoked crack 16.9 vs. 15.6, respectively, P =.96; and smoked marijuana 17.5 vs. 15.3, respectively, P =.36) and in the proportion of daily users: sniffed cocaine 10% versus 17%, respectively (P =.28); snorted heroin 47% versus 40%, respectively (P =.91); smoked crack 33% versus 37%, respectively (P =.68); and smoked marijuana 47% versus 40%, respectively (P =.41). Among street-recruited heroin and cocaine users in Harlem and the Bronx, the frequency of drug use did not increase following the events of September 11, 2001.