Drug and Alcohol Services Information System Report

October 5, 2001

Polydrug Use Among Treatment Admissions: 1998

In Brief

  • Over half of all persons admitted to substance abuse treatment reported polydrug use

  • Younger users were more likely to report polydrug use

  • Alcohol was reported as a primary or secondary substance by 72 percent of all persons admitted to treatment

Polydrug use (use of more than one substance) is a common pattern among alcohol and drug users. The Treatment Episode Data Set (TEDS) provides information on primary, secondary, and tertiary substances used by persons admitted to treatment in publicly funded facilities. Among these persons, polydrug use was more common than abuse of alcohol alone or of a single drug.

Polydrug use is a concern for several reasons. Successful treatment of polydrug use may be more difficult, and treatment programs may not be designed to address polydrug use. Because of drug interactions, polydrug users may experience more severe adverse consequences. In 1998, drug-related deaths were found to involve an average of 2.5 drugs.1

Some studies indicate that youths in particular are at risk for polydrug use. Twenty-nine percent of 12th graders reported using two or more substances simultaneously during the past year.2

Polydrug use continues into adulthood. Among persons aged 28 to 32, 31 percent used marijuana and alcohol, 28 percent used alcohol and other illicit drugs, and 22 percent used marijuana and other illicit drugs.3
Polydrug Use by Age
Over half (56 percent) of all persons admitted to treatment in publicly funded facilities reported abuse of at least one substance in addition to their primary substance (Table 1). Younger users were more likely to report polydrug use—69 percent of persons under 20 were admitted to treatment with abuse of at least two substances. Although this proportion declined with age, polydrug use occurred more frequently than single drug use until age 45.4
Primary and Secondary Use
In many analyses, people are classified according to their primary substance of abuse. This means that use or abuse of other drugs may not be considered.

Abuse of alcohol, either alone or as a secondary substance, was characteristic of most treatment admissions (Figure 1). About half of all treatment admissions were for primary alcohol abuse. However, 23 percent of persons admitted for other drugs reported that they also had an alcohol problem. Overall, 72 percent of all persons admitted to treatment abused alcohol.

Marijuana/hashish was reported as a primary substance by 14 percent of all admissions, but was a secondary substance for another 23 percent, so that 37 percent of all treatment admissions used marijuana.

Cocaine was a primary substance for 16 percent of admissions, but was a secondary substance for an additional 18 percent. Thus, one third of all treatment admissions involved cocaine abuse.

Heroin or other opiates were likely to be reported as primary drugs. Of all admissions, 16 percent reported primary opiate use, and 3 percent reported secondary opiate use, for a total of 19 percent of all admissions.

Table 1. Admissions Reporting Polydrug Use, by Age Group: 1998

Figure 1. Primary and Secondary Use of Selected Drugs: 1998

 Age group Number of admissions Percent reporting polydrug use
 Total 1,563,000 56%
   Younger than 20 years 197,000 69%
   20 to 24 years 167,000 62%
   25 to 29 years 211,000 61%
   30 to 34 years 266,000 60%
   35 to 39 years 287,000 56%
   40 to 44 years 212,000 50%
   45 years or older 223,000 35%
Figure 1. bar chart showing primary and secondary use of selected drugs

Source: SAMHSA Treatment Episode Data Set (TEDS).

Primary and Secondary Use by Age
Use of alcohol as a primary substance increased with age, from 31 percent of those under age 20 to 66 percent of those 45 or older. (Figure 2). However, use of alcohol as either a primary or secondary substance was reported by at least two thirds of persons in every age group.

Marijuana use tended to decline with age (Figure 3). Among persons under 20, primary marijuana represented 54 percent of all admissions, and marijuana was used by 81 percent of all youth admissions. Among older persons, marijuana was more likely to be a secondary problem rather than the primary reason for treatment entry.

Cocaine, like marijuana, represented a significant secondary drug problem (Figure 4). In every age group, at least as many people reported cocaine as a secondary problem as entered treatment because of primary cocaine use.

Figure 2. Primary and Secondary Alcohol Use, by Age Group: 1998 Figure 3. Primary and Secondary Marijuana/Hashish Use, by Age Group: 1998
Figure 2. Bar chart showing primary and secondary alcohol use, by age group, from under 20 years old to over 45 years old, during 1998 Figure 3. Bar chart showing primary and secondary marijauna and hashish use, by age group, from under 20 years old to over 45 years old, during 1998

Source: SAMHSA Treatment Episode Data Set (TEDS).

Figure 4. Primary and Secondary Cocaine Use, by Age Group: 1998 The Drug and Alcohol Services Information System (DASIS) is an integrated data system maintained by the Office of Applied Studies, Substance Abuse and Mental Health Services Administration (SAMHSA). One component of DASIS is the Treatment Episode Data Set (TEDS), a national-level dataset comprising State administrative data from treatment facilities receiving public funds. The TEDS system includes records for some 1.6 million substance abuse treatment admissions annually. TEDS records represent admissions rather than individuals, as a person may be admitted to treatment more than once.

The DASIS Report is prepared by the Office of Applied Studies, SAMHSA; Synectics for Management Decisions, Inc., Arlington, Virginia; and RTI International, Research Triangle Park, North Carolina.

Information and data for this issue are based on data reported to TEDS through April 16, 2001.

Access the latest TEDS reports at:
www.oas.samhsa.gov/dasis.htm

Access the latest TEDS public use files at:
webapp.icpsr.umich.edu/cocoon/SAMHDA-SERIES/00056.xml

Figure 4. Bar chart showing primary and secondary cocaine use, by age group, from under 20 years old to over 45 years old, during 1998

Source: SAMHSA Treatment Episode Data Set (TEDS).

End Notes
1 Substance Abuse and Mental Health Services Administration. (2000). Drug Abuse Warning Network: Annual medical examiner data 1998 (Drug Abuse Warning Network Series: D-13. DHHS Publication No. SMA 00-3408). Rockville, MD: Author.

2 Collins, R.L., Ellickson, P.L., & Bell, R.M. (1998). Simultaneous polydrug use among teens: Prevalence and predictors. Journal of Substance Abuse, 10, 233-253.

3 Earleywine, M., & Newcomb, M.D. (1997). Concurrent versus simultaneous polydrug use: Prevalence, correlates, discriminant validity, and prospective effects on health outcomes. Experimental and Clinical Psychopharmacology, 5, 353-364.

4 After age 55, polydrug abuse may become "polypharmacy abuse" because the number of drugs prescribed for an individual typically increases with age. A separate issue on drug treatment admissions for individuals aged 55 or older will be published in November, 2001.

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