Illegal drug use and its correlates in San Juan, Puerto Rico

•Household survey of the population 18–64 years of age in San Juan, Puerto Rico.•The overall rate of 12-month drug use in San Juan, Puerto Rico, was 16.5%.•The two drugs most used were marijuana and opiates.•Male gender, age 18–39, no religion were associated with a higher drug use rate.•Lower family cohesion and lower income were associated with a higher drug use rate. Data on the prevalence and correlates of illegal drug use in Puerto Rico are now almost 20 years old. This study sought to estimate the 12-month prevalence of illegal and non-prescribed medical drug use in San Juan, Puerto Rico and identify sociodemographic correlates of use. Data are from a random household sample of 1510 individuals, 18–64 years of age in San Juan, Puerto Rico. The 12-month prevalence of any illegal or non-prescribed drug use was 16.5%. Prevalence among men (20.7%) was higher than among women (12.9%; chi2 = 16.308; df = 1; p