In this study, we estimate a hypothesized link from early onset inhalant use to later use of opiates by young adulthood, with data from an epidemiological sample of 2311 first graders who entered an urban mid-Atlantic public school system in 1985 or 1986 (49.8% male; 67.1% ethnic minority), and who were studied longitudinally to young adulthood. An estimated 9% had initiated inhalant use before the age of 14 and at follow-up in young adulthood an estimated 3% (n=66) of the sample had tried opiates at least once. Youth who used inhalants prior to age 14 were twice as likely to initiate opiate use, as compared to those who had never tried (relative risk 2.2; 95% CI=1.4, 3.3). Statistical adjustment for other covariates attenuated but did not dissolve this relationship. These findings help confirm previously reported evidence that the use of inhalants might be an early marker of vulnerability for future involvement with illegal drugs such as heroin, but an exploratory analysis suggests that there may be no direct inhalants--opiate link once a general early onset susceptibility trait is taken into account.