Drug use by youth has serious and often long-term individual, social, and economic consequences. Drug use contributes to crime, decreases economic productivity, and requires a disproportionate share of health care services for those affected. Use of drugs is a preventable behavior that, when established during adolescence, can extend into adulthood.49
The effects of drug use on individual health and well-being have been well documented: for example, the use of cocaine has been linked with numerous health problems ranging from eating disorders to disability and even death from heart attack and stroke.50 Marijuana use holds both health and cognitive risks, particularly for damage to pulmonary functions as a result of chronic use.51 Hallucinogens can affect brain chemistry and result in problems both in learning new information and retaining knowledge.52 And chronic use of some inhalants may result in injury to the liver and kidneys as well as cause neurological damage, although it is not yet determined whether such damage is long term.53
Marijuana Use.54 From a high of 37.1 percent in 1978, large and steady declines in the percentage of 12th graders reporting marijuana use were evident through 1992. Since 1992, however, marijuana use in the past 30 days among 12th-grade students has increased from 11.9 percent to 23.1 percent in 1999 (see Figure SD 3.5.A). The rise in marijuana use is also evident among 8th-grade students, increasing from 3.2 percent in 1991 to 9.7 percent in 1999. Marijuana use by 10th graders rose from 8.7 percent in 1991 to 19.4 percent in 1999.
Tenth and 12th graders have consistently been more likely to use marijuana than inhalants, hallucinogens, or cocaine. As of 1994, marijuana use among 8th-grade students had surpassed prevalence rates of other drugs shown (see Table SD 3.5.A). This increase in the use of marijuana corresponds with a decline in its perceived harmfulness by students across all grade levels from 1991 to 1998.55
Differences by Age. As seen with cigarette and alcohol use (see Sections SD 3.1 and SD 3.3), use of both marijuana and hallucinogens increases with grade level. This increase is relatively small for hallucinogen use but is substantial for marijuana use. In 1999, 9.7 percent of 8th-grade students reported using marijuana in the past 30 days (see Table SD 3.5.A). More than twice that percentage of 12th graders (23.1 percent) reported using marijuana within the past 30 days in the same year. In contrast, inhalant use is more prevalent in the 8th grade than in either the 10th or the 12th grade. The rate of inhalant use among 8th graders was 5.0 percent, compared with 2.6 percent for 10th graders and 2.0 percent for high school seniors in 1999. The prevalence of cocaine use is lowest among 8th graders in 1999 (1.3 percent), but similarly small rates are reflected in other grades as well (1.8 percent for 10th grade and 2.6 percent for 12th grade) (see Table SD 3.5.A).
Use of Other Specified Drugs. Increases have also been shown in the use of cocaine and hallucinogens since 1991 across all grade levels. In recent years, cocaine use has been least prevalent among the four drugs types examined in this section among all grade levels, with a high of 2.6 percent of 12th-grade students reporting use within a 30-day period in 1999 (see Figure SD 3.5.B). Hallucinogens have low prevalence rates among 8th graders in 1999 (1.3 percent), although use increases with grade, eventually surpassing the use of inhalants for the upper grade levels. The use of inhalants is highest among 8th-grade students at 5.0 percent in 1999 (see Table SD 3.5.A).
One-quarter (25.9 percent) of America’s 12th graders report use of “any illicit drug” in the
past 30 days in 1999, with 22.1 percent of 10th graders and 12.2 percent of 8th graders
reporting similar recent use (see Table SD 3.5.C).
Differences by Gender. Male high school students appear somewhat more likely than females to report use of marijuana, inhalants, hallucinogens, and cocaine. The largest gender difference is seen in marijuana use and is most apparent in the upper grade levels. Among 8th-grade students, 10.5 percent of males and 8.8 percent of females reported marijuana use within the preceding 30 days of the survey in 1999. In the 10th grade in that year, males reported marijuana use at about 5 percentage points higher than that of females (21.8 versus 17 percent). This gender gap is about 7 percentage points among high school seniors in 1999 (26.3 versus 19.7) (see Table SD 3.5.A).
Differences by Race. For each category of drug use shown, as well as for use of any illicit drugs, black students consistently report the lowest rates of use across all grades (see Tables SD 3.5.B and SD 3.5.C).
49 Johnson, R.A., Hoffmann, J.P., & Gerstein, D.R. July 1996. The Relationship between Family Structure and Adolescent Substance Use. Rockville, Md.: Substance Abuse and Mental Health Services Administration, Office of Applied Studies.
50 Blanken, A.J. 1993. Measuring Use of Alcohol and Other Drugs among Adolescents. Public Health Reports (Journal of the U.S. Public Health Service) 108 (Supp. 1).
51 See, for example, Marijuana: Facts Parents Need to Know, National Institute on Drug Abuse, U.S. Department of Health and Human Services, NCADI Pub. No. PHD712, 1995; and Pope, H., & Yurgelun-Todd, D., 1996, The Residual Cognitive Effects of Heavy Marijuana Use in College Students, Journal of the American Medical Association 275 (7).
52 "Measuring the Health Behavior of Adolescents: The Youth Risk Behavior Surveillance System and Recent Reports on High-Risk Adolescents." 1993. Public Health Reports 108 (Supp. 1). Rockville, Md.: Public Health Service.
53 Public Health Service, 1993.
54 These percentages likely underestimate the rate of drug use among all youth, because school-age youth who are not in school are somewhat more likely to use drugs than those in school. (Based on unpublished prevalence rates of past-month marijuana use, past-year cocaine use, and past-year inhalant use among youth ages 12 to 17, by school status, enrolled or not enrolled, from the 1994-95 National Household Surveys on Drug Abuse.)
55 The data on perceived harmfulness of specified drugs are not shown here but can also be obtained from the Monitoring the Future Study. The percentage of students who think that smoking marijuana occasionally or regularly is physically or otherwise harmful has dropped from 1991 to 1998 across all grade levels. In 1999, 23.9 percent of 12th-grade students perceived smoking marijuana occasionally to be harmful (down from 40.6 percent in 1991), and 57.4 percent perceived smoking marijuana regularly to be harmful (down from 78.6 percent in 1991).
Figure SD 3.5.A Percentage of 8th-, 10th-, and 12th-grade students in the United States who report having used marijuana within the previous 30 days: Selected years, 1975-1999
Sources: Johnston, O’Malley, and Bachman, 2000, Table 4-7; also, prior years of this publication. Additional historical data tables provided by Monitoring the Future Study staff.
Table SD 3.5.A Percentage of 8th-, 10th-, and 12th-grade students in the United States who report having used specified drugs within the previous 30 days, by grade and gender: Selected years, 1975-1999
a All data are unadjusted for underreporting of nitrites. Data for 12th grade only, based on three of six questionnaire forms, with sample size one-half of total sample size.
b All data are unadjusted for underreporting of PCP. Note: Data for 8th and 10th grades available since 1991.
Sources: Johnston, O’Malley, & Bachman, 2000. Table 4-7, pre-publication Table 4-7 for 1998, and prior years of this publication. Additional historical data tables provided by Monitoring the Future Study staff.
Table SD 3.5.B Percentage of 8th-, 10th-, and 12th-grade students in the United States who report having used specified drugs within the previous 30 days, by race and Hispanic origina: 1992-1999
a Estimates for whites and blacks include Hispanics of those races. Persons of Hispanic origin may be of any race.
b Inhalants include substances such as glues and aerosols. Data for 12th-grade students based on five of six forms. Data are unadjusted for known underreporting of nitrites.
c Hallucinogens include substances such as LSD. Data are unadjusted for known underreporting of PCP.Note: Estimates represent the mean of the specified year and the previous year. Data have been combined to increase subgroup sample sizes, thus providing more stable estimates.
Sources: Johnston, O’Malley, & Bachman, 1998, Table 4-9. Also, prior years of this publication (Table 10 for 1992-1995, Table 4-9 thereafter). Prepublication Table 4-9 for 1998 provided by Monitoring the Future Study staff.
Figure SD 3.5.B Percentage of 12th-grade students in the United States who report having used specified drugs within the previous 30 days: 1975-1999
a All data on inhalants are unadjusted for underreporting of nitrites.
b All data on hallucinogens are unadjusted for underreporting of PCP.
Sources: Johnston, O’Malley, & Bachman, 2000, Table 4-7. Also, prior years of this publication. Additional historical data tables provided by Monitoring the Future Study staff.
Table SD 3.5.C Percentage of 8th-, 10th-, and 12th-grade students in the United States who report having used any illicit drugsa in the previous 30 days, and 12th-grade reports of illicit drug use by gender and by race and Hispanic origin: Selected years, 1985-1999
a For 12th graders only: Use of “any illicit drug” includes any use of marijuana, LSD, other hallucinogens, crack, other cocaine, or heroin, or any use of other opiates, stimulants, barbiturates, or tranquilizers not under a doctor’s orders. For 8th and 10th graders only: The use of other opiates and barbiturates has been excluded, because these younger respondents appear to overreport use (perhaps because they include the use of nonprescription drugs in their answers).
b Estimates for whites and blacks include Hispanics of those races. Persons of Hispanic origin may be of any race.
c Estimates for race and Hispanic origin represent the mean of the specified year and the previous year. Data have been combined to increase subgroup sample sizes, thus providing more stable estimates. Note: Data for 8th and 10th grades available since 1991.
Sources: Johnston, O’Malley, & Bachman, 2000, Table 2-1b. Some data for 1998: The Monitoring the Future Study, The University of Michigan. Drug Use among American Young People Begins to Turn Downward. Press release of December 18, 1998, Table 1b. 1119: pre-publication tables 4-7 and 4-9 provided by Monitoring the Future Study staff.