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Drug abuse

Alternative names

The use of illicit drugs or the abuse of prescription or over-the-counter drugs for purposes other than those for which they are indicated or in a manner or in quantities other than directed. See also drug abuse first aid and drug abuse and dependence .



Marijuana ("grass"; "pot"; "reefer"; "joint"; "hashish"; "cannabis"; "weed")

About 1 in 3 Americans has used marijuana at least once and approximately 10% of the population uses it on a regular basis. Next to tobacco, and alcohol in some areas, marijuana is the most popular substance chosen by young people for regular use.

The source of marijuana is the hemp plant (cannabis sativa) and its content of THC (delta-9-tetrahydrocannabinol) and other cannaboids found in the leaves and flowering shoots of the plant.

Hashish is a resinous substance, taken from the tops of female plants, which contains the highest concentration of THC. The drug dose delivered from any particular preparation of marijuana greatly varies. The concentration of THC may vary as much as a hundred fold, due to diluents or contaminants in the sample.

The effects of marijuana may be noted within seconds to several minutes after inhaling the smoke (from a joint or a pipe) or within 30 to 60 minutes after ingestion (eating foods containing marijuana such as brownies).

Because the effects are felt almost immediately by the smoker, further inhalation can be stopped at any time and the effect therefore regulated. In contrast, those ingesting marijuana experience effects that are slower to develop, cumulative, longer lasting, and more variable, making unpleasant reactions more likely with this method of administration.

The primary effects of marijuana are behavioral, because the drug affects the central nervous system (CNS). Popular use of marijuana has arisen from its effects of euphoria, sense of relaxation, increased visual, auditory, and taste perceptions that may occur with low to moderate doses of the drug. Most users also report an increase in their appetite ("munchies").

Unpleasant effects that may occur include depersonalization, changed body image, disorientation and acute panic reactions or severe paranoia . Some cases of severe delirium and hallucinations have also been reported. Such cases should raise suspicion that the marijuana may have been laced with another agent such as PCP.

Marijuana has specific effects that may decrease one's ability to perform tasks requiring a great deal of coordination (such as driving a car). Visual tracking is impaired and the sense of time is typically prolonged.

Learning may be greatly affected because the drug diminishes one's ability to concentrate and pay attention. Studies have shown that learning may become "state-dependent" meaning that information acquired or learned while under the influence of marijuana is best recalled in the same state of drug influence.

Other marijuana effects may include blood-shot eyes; increased heart rate and blood pressure ; bronchodilatation, or in some users, bronchial irritation leading to bronchoconstriction and/or bronchospasm; pharyngitis , sinusitis , bronchitis , and asthma in heavy users; possible detrimental effects upon the immune system.

Regular users, upon discontinuation of marijuana, may experience withdrawal effects. These may include agitation , insomnia , irritability, and anxiety . Because the metabolite (the substance formed when the body breaks marijuana down) of marijuana may be stored in the body's fat tissue, evidence of marijuana may be demonstrated through urine assay testing up to 1 month after discontinuing the drug in heavy users.

The active component in cannabis is believed to have medical properties. Many maintain that it is effective in the treatment of nausea caused by chemotherapy in cancer patients.

Others claim that cannabis stimulates appetite in patients with AIDS or is useful in the treatment of glaucoma. While the active ingredient in marijuana has been approved as a synthetic medication by the FDA (dronabinol) for these purposes, use of whole marijuana remains hugely controversial. Currently, cannabis is illegal even for medical use under federal law.

Phencyclidine (PCP) "angel dust"

It is difficult to estimate the current use of phencyclidine in the United States because many individuals do not recognize that they have taken it. PCP is frequently laced with other illicit substances (such as marijuana) and the buyer not made aware of its presence.

A 1986 National Institute of Drug Abuse survey of high school seniors revealed that over 12% of the students had used hallucinogens and that many of these drugs probably contained PCP.

PCP use in the U.S. dates back to 1967 when it was sold as the "Peace Pill" in the Haight-Ashbury district of San Francisco. Its use never became very popular because it had a reputation for causing "bad trips."

PCP use grew during the mid-1970s primarily because of different packaging (sprinkling on leaves that are smoked) and marketing strategies. During the 1980s it was established as the most commonly used hallucinogen, with the majority of users 15 to 25 years old.

Although phencyclidine was initially developed by a pharmaceutical company searching for a new anesthetic, it was not suitable for human use because of its psychotropic side effects.

PCP is no longer manufactured for legitimate, legal purposes. Unfortunately it can be made rather easily and without great expense by anyone with a basic knowledge of organic chemistry, making it a prime drug for the illicit drug industry. It is available illegally as a white, crystalline powder that can be dissolved in either alcohol or water.

PCP may be administered via different routes. The onset of effects is related to the means of drug administration. If dissolved, PCP may be taken intravenously and effects noted within seconds.

Sprinkled over dried parsley, oregano, or marijuana leaves, it can be smoked and effects noted within 2 to 5 minutes, then peaking at 15 to 30 minutes. Taken orally, in the pill form or mixed with food or beverages, PCP's effects are usually noted within 30 minutes and tend to peak at about 2 to 5 hours.

Lower doses of PCP typically produce euphoria and decreased inhibition as may be seen with drunkenness. Mid-range doses cause body wide anesthetic with enhanced sensations and impaired perceptions which may result in panic reactions and violent defensive behaviors.

Large doses may produce paranoia, auditory hallucinations, psychosis similar to schizophrenia . Massive doses, more commonly associated with ingesting the drug, may cause cardiac arrhythmias , seizures , muscle rigidity , acute renal failure , and death. Because of the analgesic properties of PCP, users who incur significant injuries may not feel any pain.

Ketamine, a compound related to PCP, has grown in popularity in recent years. It is commonly referred to as Special K.


In addition to PCP, other commonly abused hallucinogens include LSD (lysergic acid diethylamide), Psilocybin (mushrooms, "shrooms"), and Peyote (a cactus plant containing mescaline).

The use of naturally occurring hallucinogens, specifically for religious rites, has been documented for centuries. Mushrooms containing psilocybin were used by the native people of Mexico and peyote use was common amongst some Southwest American Indian tribes.

In contrast, LSD is a man-made substance, first developed by a legitimate pharmaceutical company in 1938. Today, most hallucinogens are used experimentally rather than on a regular basis, with only single or several uses per year reported by most users.

LSD is an extremely potent hallucinogen with only minuscule doses required to produce effects. Compared to LSD, psilocybin is 100 to 200 times less potent and mescaline (peyote) is about 4,000 times less potent.

Hallucinogens are commonly associated with panic attacks at the height of the drug experience ("bad trips"). Unsolicited repetitions of the drug experience, without further ingestion of the drug ("flashbacks"), may also occur in rare cases. Such experiences typically occur during times of increased stress and tend to decrease in frequency and intensity if the individual abstains from use of the drugs.

Stimulants ("speed"; "crack"; "coke"; "snow"; "crank"; "go"; "speedball"; "crystal"; "cross-tops"; "yellow jackets")

The abuse of cocaine increased dramatically in the late 1980's and early 1990's but is now on the decline.

Cocaine may be inhaled through the nose ("snorting") or dissolved in water and administered intravenously. When mixed with heroin , in a single syringe for IV use, the combination is referred to as a "speedball."

Through a simple chemical procedure, cocaine may be changed into a smokeable form known as freebase or "crack." Smoking produces an instant and intense euphoria attractive to abusers. Other effects include local anesthesia, potent CNS stimulation, feelings of increased confidence, energy, accompanied with decreased inhibitions.

Increased use and dependence to cocaine are probably related to its specific characteristics of producing an extremely pleasurable high that is very short lived. This prods the drug abuser into more frequent or regular use to attain the desired mood.

Both tolerance and dependence may occur with chronic use of cocaine. . Regular users may exhibit mood swings, depression , sleep problems, memory loss, social withdrawal, and loss of interest in school, work, family, and friends. Because heavy use may cause paranoia, cocaine users may become violent.


During the 1950s through 1960s, amphetamines were commonly prescribed for conditions such as fatigue , obesity , and mild depression. Such use has ceased as their highly addictive potential became apparent and they have been categorized as controlled substances.

Over-the-counter (OTC) amphetamine look-alike drugs (typically containing caffeine and/or phenylpropanolamine and marketed as appetite suppressants or stay awake/alert aids) are commonly abused.

If taken in high doses, these OTC drugs may cause the same high and other effects associated with amphetamines. Regular users may exhibit irritability, restlessness , sleep disturbances , tremors , dilated pupils, skin flushing , and weight loss over time.


Inhalant abuse became popular with young teens in the 1960s with "glue sniffing." Since that time, a broader variety of inhalants have been popularized. Inhalant use typically involves younger adolescents or school-age children and occurs primarily as experimental behavior within groups of peers.

Commonly abused inhalants include model glue, spray paints, cleaning fluids, gasoline , liquid typewriter correction fluid, and aerosol propellants for deodorants or hair sprays.

The chemicals are poured into a plastic bag or soaked into rags, then inhaled. Since the drugs are absorbed through the respiratory tract an altered mental state is noted within 5 to 15 minutes.

Adverse effects which have been associated with inhalant abuse include liver or kidney damage , convulsions , peripheral neuropathy , brain damage, and sudden death. Most inhalant use occurs amongst teens or preteens who do not have access to illicit drugs or alcohol.

Opiates, Opioids, and Narcotics

Opiates are derived from opium poppy. These include morphine and codeine. Opioids refer to synthetically produced substances that have the same effect as morphine or codeine.

These include heroin, oxycodone, hydromorphone , meperidine, propoxyphene, and methadone. All of these substances, natural or synthetic, are considered narcotics. As analgesics these drugs produce an altered interpretation of painful stimuli , decrease anxiety, and promote sedation.

Because heroin is commonly used intravenously, the associated health concerns specific to IV drug use and sharing needles or using contaminated needles (such as hepatitis , HIV infection, and AIDS ) must be considered.


Several stages of drug use and their characteristics have been described. Progression through the stages seems to be accelerated in juveniles when compared to adult drug abusers.

  • Experimental use -- typically involves peers, recreational use; the user may enjoy defying parents or other authority figures.
  • Regular use -- increased school or work absenteeism; worries about loosing source; uses drugs to "remedy" negative feeling; begins to isolate from friends and family; may change peer group to others who are regular users; and takes pride in noting increased tolerance and ability to "handle" the drug.
  • Daily Preoccupation -- loss of motivation; indifference towards school and work; behavior changes become evident; preoccupation with drug use supersedes all prior interests including relationships; secretive behavior; may begin dealing drugs to help support habit; use of other, harder drugs may increase, legal complications may increase.
  • Dependency -- cannot face daily routine without aid of drugs; continued denial of problem; deteriorating physical condition; loss of "control" over use; may become suicidal; financial and legal complications worsen; and may have severed ties with family members or friends by this time.


Support groups and counseling should be tried first -- as with any other area of medicine, the least intensive treatment should be the starting point.

Comprehensive residential treatment programs monitor and address potential withdrawal symptoms/behaviors; incorporate behavior recognition and modification programs; include psychotherapeutic treatments both for the person (and perhaps family) and in group settings; have a prolonged after-care component; and facilitate peer support.

Drug addiction is a serious and complicated health condition that requires both physiological and psychological treatment and support.


  • if concerned about the addictive potential of currently prescribed medications.
  • if concerned about possible drug abuse by self or a family member.
  • if interested in more information regarding drug abuse.
  • if seeking treatment of drug abuse for self or a family member.
Also seek out information and support from local 12-step support groups (such as Alcoholics Anonymous (AA), Narcotics Anonymous (NA), and Ala-teen-Alanon) or other support groups like SMART Recovery, Moderation Management and LifeRing Recovery. See alcoholism - support group , chemical dependence - support group .

Update Date: 3/8/2002

Benoit Dubé, M.D., Department of Psychiatry, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network.

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Last updated: Tue, 06 Jan 2009 00:20:03 GMT