Drug Abuse

  • Basics

    Drug abusers use substances to modify their mood or state of mind, even when doing so causes difficulties at work, school, or with relationships, health, or the law. Substance abuse contributes to many social ills, including crime, accidents, and family violence. For example, substance abuse causes impaired judgment, which may lead to the spread of HIV through needle-sharing and trading sex for drugs. Drug-related problems cost an estimated $160 billion or more annually.

    Drug dependence and tolerance are different from drug abuse or addiction. Physical tolerance occurs when a person needs additional amounts of a drug to achieve the same effect as a lower dose had previously caused. Dependence occurs when a person becomes adapted to a drug, and experiences symptoms of withdrawal if the drug is not taken. A dependent person may not be able to control the amount of substance they consume, or be able to stop using the drug. In addition, the unpleasant physical and behavioral withdrawal symptoms often drive them back to using the substance. People can be addicted to drugs, such as cocaine, that do not produce physical dependence. In addition, cancer patients who require increasing amounts of narcotic pain relievers may develop a tolerance, but are not considered to be addicted if they do not exhibit the behavioral symptoms of addiction.

    Tolerance, dependence, abuse, and addiction can occur with over-the-counter, prescription, or illegal substances. Multiple substances are often used in tandem. Drug abusers tend to deny substance-related problems, under-report their intake, and attempt to hide their addictions.

    Drugs that are commonly abused include alcohol and nicotine, marijuana, opiates (heroin and Talwin), psychostimulants (cocaine), sedative-hypnotics (benzodiazepines and barbiturates), hallucinogens (LSD), phencyclidine (PCP), designer drugs (Ecstasy), and inhalants.

    People who abuse one drug are at high risk for abusing other chemical agents. Often drug abusers will use multiple drugs simultaneously. A tolerance for one drug usually causes a tolerance for other drugs in the same class.

    Patients who abuse prescription drugs may take the drugs for different purposes, or more frequently than the doctor prescribed.

    While many people experiment with drugs, not as many make drug use a regular habit.A report by the Substance Abuse and Mental Health Association found that overall illicit drug use, particularly use of marijauna, ecstasy, and heroin has decreased from 11.6% in 2002 to 9.9% in 2005 in youth aged 13-17 years old. Though this shows improvement, it is still alarming to talk about heroin use in teen-agers. The same report showed a very high overall use of prescription drugs, such as tranquilizers and narcotic pain relievers, in teen-agers. The study showed that 6.4 million people aged 12 and older abused prescription drugs in the month that the survey was taken.

    Drug abusers suffer from an array of medical and mental illnesses Table 01. Untreated abusers—health care costs are about twice those of users who have received treatment.

    Anxiety, depression, insomnia, phobias, and emotional and behavioral problems frequently coexist with drug abuse or result from the substance use. Drug abusers are two to four times more likely than non-drug users to have a psychiatric disorder. Patients with a mental illness often use drugs to self-medicate in hopes of limiting their symptoms.

    Table 1.  Medical Illness Associated With Chronic Drug Dependence

    Substance Illness
    Cannabis Respiratory disorders, decreased pulmonary function, possible increased risk of emphysema and pulmonary cardiac arrest, cardiac conduction abnormalities, premature ventricular contractions, decreased sperm count and motility, menstrual abnormalities
    Stimulants Sudden death, cardiac arrhythmias, fibrillation, infarction, hypertensive crisis, hyperthermia, pulmonary edema, physical exhaustion, epistaxis, nasal septum perforation, chronic rhinitis, chronic pulmonary infections, and pulmonary alveolar damage (smoking) with nasal use, systemic infection, endocarditis, central nervous system abscess, granulomas, injection site cellulitis, and blood-borne virally transmitted disease (HIV, hepatitis) with intravenous use
    Opiates Increased risk of tuberculosis, generalized malnutrition, transmission of blood-borne viruses (HIV, Epstein-Barr virus, hepatitis), staphylococcal endocarditis, systemic bacterial infections, foreign body emboli, pulmonary fibrosis, abscess, and injection site fibrosis or abscess with intravenous use
  • Causes

    Neurochemical changes resulting from drug use contribute to addiction and abuse. Addictive drugs create complex changes in the brain's reward system, contributing to physical and psychological dependence, fear of withdrawal, and memory alteration. Cues from this altered reward system stimulate desire for another hit of the drug. Wanting a cigarette after a large meal or after sex are two such examples.

    Some substances possess reinforcing qualities that make them more addictive. Smoking or injecting a drug, for example, typically produce more powerful results than swallowing a pill, making those drugs that are smoked or injected more reinforcing and addicting. However, substances with low-reinforcing qualities frequently become a problem for people with a biological or genetic predisposition to them, or for those who use the substance regularly.

    Easy access, and environmental, psychological, and cultural factors play a role in who starts or continues to abuse drugs. People who become addicted frequently exhibit immaturity, frustration, and difficulty solving problems or relating to people of the opposite sex. These people often lack self-esteem. Addicts frequently have a dependent personality, seeking support from others. Some are prone to rage and uncontrolled behavior.

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