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Symptoms and Signs of Drug Dependence and Abuse

Doctor's Notes on Drug Dependence and Abuse

Drug abuse (substance abuse) is an intense desire to use increasing amounts of a particular substance, or to take illegal drugs or to misuse legal substances such as alcohol or prescription medications. Drug dependence (addiction) is the body's physical need to have a specific drug. Over time, dependence results in physical harm, behavior problems, and association with people who also abuse drugs. Stopping the use of the drug can result in withdrawal symptoms.

Symptoms of drug dependence and abuse depend on the substances being abused. Symptoms of drug dependence and abuse may include changes in the level of consciousness, a decrease in responsiveness, bizarre behavior, agitation anger, anxiety, sleep problems, hallucinations, sleepiness, confusion, skin is cool and sweaty or hot and dry, chest pain, abdominal pain, nausea, vomiting, and diarrhea. Serious symptoms of drug dependence and abuse include coma, abnormal vital signs (temperature, pulse rate, respiratory rate, blood pressure), vomiting blood, blood in bowel movements, and a person may stop breathing, which can cause death. Withdrawal symptoms vary depending on the drug but can be life threatening.

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 3/11/2019

Drug Dependence and Abuse Symptoms

The signs and symptoms displayed by a person depend on what substances the person has abused. A person who has not abused drugs extensively may experience unpleasant symptoms and may seek help from family members and friends. Chronic drug abusers generally know what to expect from their drug use and rarely seek help for themselves.

  • Most agents cause a change in level of consciousness -- usually a decrease in responsiveness. A person using drugs may be hard to awaken or may act bizarrely.
  • Suppression of brain activity can be so severe that the person may stop breathing, which can cause death.
  • Alternatively, the person may be agitated, angry, anxious, and unable to sleep. Hallucinations are possible.
  • Abnormal vital signs (temperature, pulse rate, respiratory rate, blood pressure) are possible and can be life threatening. Vital sign readings can be increased, decreased, or absent completely.
  • Sleepiness, confusion, and coma are common. Because of this decline in alertness, the drug abuser is at risk for assault or rape, robbery, and accidental death.
  • Skin can be cool and sweaty or hot and dry.
  • Chest pain is possible and can be caused by heart or lung damage from drug abuse.
  • Abdominal pain, nausea, vomiting, and diarrhea are possible. Vomiting blood, or blood in bowel movements, can be life threatening.
  • Withdrawal syndromes are variable depending on the agent but can be life threatening.
  • People with drug dependency often develop a tolerance to their drug of choice in that it takes more of the substance over time to achieve the desired effect.
  • Sharing IV needles among people can transmit infectious diseases, including HIV (the virus that causes AIDS) and hepatitis types B and C.
  • Many common household drugs and chemicals can be abused. Gasoline and other hydrocarbons are frequently abused by adolescents and preadolescents as inhalants. Over-the-counter drugs, such as cold medications, are commonly taken in excessive doses by adolescents and young adults to get high. Prescription medications are additional examples of drugs that are abused and that can be obtained illegally (without a prescription).
  • Amphetamines and cocaine cause impotence in men. Sildenafil (Viagra) has been used by users of cocaine, methamphetamine, and other and amphetamines to counteract impotence. Because Viagra is generally prescribed for middle-aged and older men, a younger person must be questioned as to why he has a need for Viagra.

There are thought to be four stages of addiction symptoms that correspond to increasing severity of the addiction: no symptoms, to wanting, craving, and needing the drug of choice.

Drug Dependence and Abuse Causes

While there is no single cause for substance abuse, people abuse drugs for a number of different reasons.

  • The most common reason why people abuse drugs is to "get high." Adolescents and preadolescents can become involved in experimentation with drugs. However, only a small percentage of people who experiment with drugs become drug abusers. The desire to get high may be from an underlying psychological disease such as depression. Other risk factors for drug use also include the pressures of coping with school, work, or family tensions.
  • Drug abuse by pregnant women results in the developing fetus (baby) being exposed to these same drugs. The baby may develop birth defects. The baby may be born with an addiction and go into withdrawal. The baby may be born with a disease associated with drug abuse such as HIV/AIDS.
  • People with current or a history of specific medical conditions, such as chronic pain from cancer, can become dependent on certain drugs. Many psychiatric diseases can be complicated by substance abuse. Similarly, drug abuse may be a sign of a more serious mental health problem. Individuals who fit the diagnostic criteria for both a substance abuse and another mental health disorder are often referred to as having a dual diagnosis.
  • Athletes have abused a variety of agents, such as steroids, to enhance muscle mass or improve athletic ability. Athletes have also abused amphetamines to make them feel more powerful and to mask pain so they can continue to play even with injuries. Drug testing programs have reduced this problem to some extent, but drug use among athletes is still an issue worldwide.

Teen Drug Abuse Warning Signs, Statistics, and Facts Slideshow

Teen Drug Abuse Warning Signs, Statistics, and Facts Slideshow

Drug abuse, now also referred to as drug use disorders, refers to using substances, over-the-counter (OTC) medications, prescription drugs, or illegal street drugs for the purpose of getting high. Substance abuse can lead to significant, even life-threatening, health problems. It also increases the risk of accidents, suicide, unsafe sex, and violence. Teens are more likely to abuse substances if they suffer from depression, low self-esteem or impulse control, have a history of being abused, or family history of substance abuse. Teens who receive low parental supervision or communication, or who feel different than their peers are also at risk for drug abuse.

Opioid Dependence : Test Your IQ of Opioid Misuse Disorder Quiz

Opioid Dependence Quiz

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Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.