TABLE 1.

Summary of studies on the association between nonmedical prescription stimulant use and other illicit drug use

Author	Sample	Findings regarding the association between nonmedical use of prescription stimulants and illicit drug use
Arria, et al. (2008)⁵	1,253 college students	Nonmedical use of prescription stimulants is associated with past year illicit drug use, alcohol dependence, and marijuana dependence.
Barrett, Darredeau & Pihl (2006)³⁵	149 college students	72% of nonmedical prescription methylphenidate users ingested another drug simultaneously with methylphenidate.
Barrett, et al. (2005)²⁰	100 college students	Nonmedical users of prescription stimulants were more likely to have used marijuana (96% vs. 76% of those who did not use nonmedically), cocaine (60% vs. 22%), psilocybin (82% vs. 48%) and ecstasy (78% vs. 24%) in their lifetime.
DeSantis, Noar & Webb (2009)³⁶	333 college fraternity members	Nonmedical use of prescription stimulants was associated with more frequent marijuana use.
Hall, et al. (2005)³⁷	381 college students	15.4% of nonmedical prescription stimulant users used stimulants with alcohol, and 21.2% used with other drugs.
Herman-Stahl, et al. (2006)³⁸	17,709 adolescents	Use of marijuana and other illicit drugs was associated with nonmedical use of prescription stimulants.
Herman-Stahl, et al. (2007)³⁹	23,645 young adults	Binge drinking, using marijuana and using other illicit drugs was associated with nonmedical prescription stimulant use.
Low & Gendaszek (2002)⁴⁰	150 college students	Nonmedical use of prescription stimulants was associated with cocaine and ecstasy use.
McCabe, Boyd & Young (2007)⁴¹	1,086 7^th–12^th graders	58.3% of medical and nonmedical users of prescription stimulants abused an illicit drug besides marijuana, as opposed to 4.0% of non-stimulant users.
McCabe, Cranford & Boyd (2006)⁴²	43,093 adults	Binge drinking and DSM-IV criteria for alcohol abuse and dependence were significantly associated with nonmedical prescription stimulant use.
McCabe, et al. (2005)⁴	10,904 college students	Nonmedical users of prescription stimulants were more likely to have engaged in frequent binge drinking (69% vs. 21% of those who did not use prescription stimulants), marijuana use (85% vs. 27%), cocaine use (35% vs. 2%), ecstasy use (52% vs. 5%), opiate (other than heroin) use (44% vs. 6%) in the past year.
McCabe, Teter & Boyd (2006)⁶	9,161 college students	Nonmedical users of prescription stimulants were more likely to report past year binge drinking (88% vs. 49% who did not use stimulants nonmedically), marijuana use (93% vs. 34%), cocaine use (33% vs. 2%), ecstasy use (27% vs. 2%), and hallucinogen use (34% vs. 3%).
Novak, et al. (2007)⁴³	4,297 adults	Nonmedical use of prescription stimulants was associated with past month binge drinking, past year marijuana use and past year cocaine use.
Schepis & Krishnan-Sarin (2008)⁴⁴	18,678 adolescents aged 12–17	Nonmedical use of prescription stimulants was associated with past year use of alcohol, tobacco, marijuana, cocaine and inhalants.
Teter, et al. (2003)¹⁹	2,250 college students	Nonmedical methylphenidate users were more likely to engage in binge drinking in the past two weeks (98.2% vs. 58.3% of nonstimulant users), marijuana use in the past year (100.0% vs. 29.9%) and ecstasy use in the past year (57.9% vs. 5.3%).