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U.S. Department of Health and Human Services

Archival Content: 1999-2005

HIV Prevention Among Drug Users:
A Resource Book for Community Planners & Program Managers

Types of Drugs and Their Effects

Major Types of Drugs Linked to HIV Risk

Drugs are commonly categorized into major types, based on their most prominent effects. "Opiates," such as heroin, and "stimulants," such as cocaine and crack, are two major drug types whose use have been closely linked to HIV risks. For example, crack is linked to HIV transmission by the risky sexual behaviors associated with its use. Another HIV risk-related behavior-needle sharing, or multiperson use of syringes-is directly related to how frequently a drug like heroin or cocaine is injected, and whether a person has access to sterile injection equipment. Becoming familiar with the unique features of these drugs and their effects will help prioritize and support effective HIV prevention programs that are targeted to those who use them. Exhibit A provides key information about opiates and stimulants, including the likelihood of developing dependence on them, the manner in which they are used, their physical and behavioral effects, and common symptoms that occur when use stops. However, it is important to keep in mind that drug use experiences often vary among individuals. Care should be taken not to generalize and assume that all cocaine users, for example, react to cocaine in the same manner.

Exhibit A: Heroin, Cocaine, and Crack: Characteristics and Effects

Heroin-Characteristics and Effects

"If you shoot some heroin you are high, and you just kind of sit down and mind your own business. If you shoot some cocaine... you have a desire for more, but it's basically something that will pass. But with rock... the craving for more is unbelievable."

"Heroin is so intense... you can feel it move through your body and hit your brain."

"After I became addicted to heroin, I began to use it just to not get sick... I just couldn't stand going through withdrawal again."

  • Made from morphine, which is obtained from the opium poppy.
  • High risk of developing physical and psychological dependence.
  • Can be administered by injection, sniffing (snorting), or smoking.
  • Commonly injected about three times a day (every eight hours).
  • Effects last from three to six hours.
  • Typical behaviors under the influence include sleepiness ("nodding") after injection, sedate behavior, docile appearance, and shuffling gait.
  • Acute withdrawal symptoms begin within 8 to 12 hours after last dose.
  • Withdrawal is severe, although generally not life-threatening.
  • Withdrawal symptoms include severe gastrointestinal distress, muscle cramping, and other flu-like symptoms. Heroin users call this withdrawal being "drug sick." When these withdrawal symptoms are severe enough, individuals addicted to heroin want to obtain and inject the drug as rapidly as possible, sometimes without concern for possible HIV risks.
  • High risk of HIV transmission when administered by previously used, blood-contaminated needle and syringe.

Cocaine-Characteristics and Effects

"The immediate rush from cocaine was intense. I was powerful. But then I crashed and all I wanted was some more."

"I was invincible with cocaine... until I came down and the depression hit."

  • The most potent of the stimulants.
  • High risk of developing physical and psychological dependence.
  • Can be administered by smoking, or "freebasing" (onset of effect: less than 10 seconds), injection (onset of effect: 15-20 seconds), or snorting (onset of effect: 2-4 minutes).
  • Effects last from 10 to 40 minutes, depending on purity and route of administration.
  • Typical behaviors under the influence include hyperactivity, elation, increased energy and alertness, and increased sexual activity. The user may feel invincible, and is often difficult to deal with and quarrelsome.
  • Withdrawal symptoms occur within several hours after last use and result in agitation and depression.
  • High risk of HIV transmission through multiple injections when administered by previously used, blood-contaminated needles and syringes, and through unprotected, prolonged sexual intercourse.
  • Sold in ready-to-use crystals that, when heated and smoked, cause a "crackling" sound.

Crack-Characteristics and Effects

"After my first high on crack, I knew I needed to find that same feeling again."

  • Crack is prepared by heating cocaine, water, and bicarbonate (baking soda). This treatment chemically changes cocaine into a smokable form. Cost is lower than freebase cocaine (also smoked), making it more accessible.
  • Use is now widespread in some urban and rural areas among both women and men.
  • Results in an intense "rush" in a matter of seconds.
  • Effects are short-lived (a few minutes), resulting in repeated use to achieve the initial rush again and to avoid severe post-cocaine depression.
  • Typical behaviors under the influence include intense agitation and erratic activity, mood swings, confusion and disorientation, facial and body twitching ("tweaking"), and preoccupation with obtaining the next dose of crack.
  • Dependence on crack is thought to develop more rapidly than dependence on heroin or other forms of cocaine.
  • Crack sale and use can spread rapidly with devastating effects, including an increase in related violence, crime, and the exploitation of users, especially women.
  • Crack use is associated with increased sexual activity, often performed with little regard for HIV risks. As with cocaine use, male sexual performance is often affected due to delayed ejaculation, and results in prolonged intercourse with increased risk of genital injury and bleeding.

Sources: Ratner, 1993; client interviews submitted by HPDU Resource Book subject matter experts; and interviews conducted with drug users in drug treatment programs in the metropolitan Washington DC area, 1995.

The Range of Drug-Using Behaviors

Drug users commonly use more than one drug. This is often referred to as "polydrug" use. For instance, many injection drug users (IDUs) often use a combination of alcohol, marijuana, cigarettes, and crack in addition to the drug they inject. Heroin users often inject a combination of heroin and cocaine, known as a "speedball." Those who inject cocaine sometimes use heroin to alleviate the agitating effects of cocaine.

The most common reasons for multiple drug use include:

  • the desire to experience a new or different type of drug-induced effect, such as that produced when heroin and cocaine are combined to make a "speedball"
  • the need to "self-medicate," that is to balance the effects of a particular drug (e.g., using alcohol to reduce the agitation brought on by the use of a stimulant like methamphetamine)
  • the need to offset the symptoms caused by ending the use of a particular drug, such as the nausea and tremors resulting when heroin use is stopped
  • substitution of another drug when the preferred drug of choice is either difficult to obtain or too costly
  • the desire to experiment with a variety of drugs

Individuals' drug-using behaviors also can vary in intensity and frequency. Some individuals may begin to use drugs and then rapidly progress to chronic use, while others may start and stop their use with or without the assistance of drug treatment. This fluctuation in drug-using behaviors among people is an important concept to consider when prioritizing or designing HIV intervention programs. For example, a person with a long history of chronic heroin injection may not benefit from an HIV intervention that is abstinence-based. Initially, this person might fare better if offered counseling and education related to needle and syringe disinfection, ways to access sterile needles and other injection equipment, and referral to drug treatment.

Many factors contribute to these variations in drug-using behaviors. For example, drugs such as crack may cause someone with little or no history of prior drug use to quickly become dependent and begin to experience related social problems. However, frequency of drug use is not always directly related to the extent of drug-related problems encountered. A daily heroin user, for example, may be able to support his or her habit and maintain a job, while an occasional cocaine user may suffer numerous personal problems, including job loss and family disruption. Case Example 1.1 provides several personal accounts of various kinds of drug-using behaviors and some associated consequences.

Use of multiple drugs and the range of drug-using behaviors demonstrate the individualized character of drug use. This directly affects those who prioritize programs for drug users and who work with clients. Ultimately, programs for drug treatment, HIV prevention, or to support other needs must respond to individual drug users' behaviors and risks.

Case Example 1.1

Individual Accounts of Drug-Using Behaviors and
Associated Consequences

"I went to jail for prostitution...trying to get money for my drugs."
20-year-old male from Seattle

"Every time I went into treatment, I thought it would be my last time,
but I always started using again. I just couldn't help it."
44-year-old artist from San Francisco

"The police came and took away my children and put them in foster homes
until I went to treatment."
25-year-old mother from Nashville

"My daughter used heroin for ten years without losing her job, and then she
died of an overdose. Now I'm raising her kids."
68-year-old grandmother from Southside Chicago

"When I was smoking crack, there were no rules. I even stole from my family."
17-year-old Miami woman

"I lost my job, my house, and my marriage after becoming addicted to cocaine."
38-year-old accountant from San Juan

Source:Client interviews submitted by HPDU Resource Book subject matter experts,1995.

Major Patterns and Trends in Drug Use

In addition to an understanding of drug-use behaviors on an individual level, a thorough understanding of the patterns and trends in drug use within communities will support more effective approaches to HIV prevention. These more general patterns and trends result from a variety of factors, such as changes in supply and demand or changes in the drugs themselves. The following examples illustrate:

  • Changes in Supply and Demand. Crack cocaine was essentially unknown until the mid-1980s. From the mid-1980s through the early 1990s, however, crack was introduced into local drug markets of American cities and rapidly became one of the dominant forms of drug use (Miller et al., 1990).
  • Changes in Drug Quality. In the early 1990s, there was an increase in the purity of heroin marketed in the U.S. The most important consequence of this trend is that the higher purity has allowed heroin-dependent drug users to consume it by sniffing (also called "snorting") instead of injecting (Ray et al., 1996). Low-purity heroin usually is injected because it has a relatively limited effect when snorted or smoked. Because snorting does not involve syringes and avoids the possibility of transferring blood during drug injection, it usually reduces the risk of HIV transmission. On the other hand, increased purity has been associated with a rise in emergency room visits and overdoses resulting in death. It is important to note that experience with earlier heroin "epidemics " suggests that many of the current heroin snorters may eventually shift to injecting heroin, particularly if the purity of heroin drops to the levels seen in the early 1980s. In addition to understanding changes in drug supply and quality, prevention planners and program managers need to recognize regional and local patterns and trends that affect drug use. For example, a new trend that may affect drug use and HIV prevention in the mid-1990s is the increasing use of amphetamines in Western states and the introduction of amphetamines into the Midwest and South, where amphetamine use was previously uncommon (Johnson, Bassin, and Shaw, Inc., 1995, vol. II). Table 1.1 illustrates some of the variation in drug use patterns in the United States. This variation reinforces the need to incorporate local data into the prevention planning process.1
Table 1.1: Regional Patterns and Trends of Drug Use

In 1994, the National Institute on Drug Abuse-supported Community Epidemiology Work Group (CEWG), reported the following regional patterns and trends related to drug use in the US:

  • cocaine use, including crack, remains the most common substance on the drug market in Atlanta
  • New York City, Newark, Boston, and Chicago report that heroin use is either increasing or, at least, has stabilized at high levels
  • while most heroin users are over age 30, cities including Atlanta, Miami, and Chicago report an increase in younger users
  • the current purity of heroin in St. Louis is the highest ever seen in the Midwest
  • cocaine remains readily available in Denver and its use is increasing in Honolulu
  • increasingly, cocaine abusers in Miami are also snorting heroin
  • methamphetamine is the most widely used illicit drug in San Diego
Source:Johnson,Bassin,and Shaw, 1995, vol.II.

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  1. Developing an accurate picture of local drug use is discussed in greater detail later in PART 1 in the section entitled "Estimating the Extent of Local Drug Use."

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