"In conclusion, this study found that chronic drug use was significantly related to employment status for men and women. On the other hand, male chronic drug users were less likely to participate in the labor force, but no significant relationship existed between chronic drug use and labor force participation for females. Perhaps the most important finding of this study, however, was the lack of any significant relationships between nonchronic drug use, employment, and labor force participation. An implication of this finding is that employers and policy makers should focus on problematic drug users in the same way that they focus on problematic alcohol users."

Source

French, Michael T., M. Christopher Roebuck, and Pierre Kebreau Alexandre, "Illicit Drug Use, Employment, and Labor Force Participation," Southern Economic Journal (Southern Economic Association: Oklahoma State University, Stillwater, OK, 2001), 68(2), p. 366.
http://www.jstor.org/pss/1061…