Substance Abuse

Drugs are chemicals that affect the body and the brain. Different drugs can have different effects. Some effects of drugs include health consequences that are long-lasting and permanent. They can even continue after a person has stopped taking the substance. 

Addiction is a chronic disease characterized by compulsively seeking and using drugs. This compulsion is difficult to control, despite the harmful consequences. Alcohol is the most frequently used and misused substance in the United State. Alcohol misuse is especially problematic among youth and college-aged populations.

There are a few ways a person can take drugs, including injection, inhalation, and ingestion. The effects of the drug on the body can depend on how the drug is delivered. For example, the injection of a drug directly into the bloodstream has an immediate impact, while ingestion has a delayed effect. No matter how the drug is taken, all misused drugs affect the brain.

Despite knowing the negative outcomes, many people who use drugs continue to take them. This is the nature of addiction. Today, more than 7 million people suffer from an illicit drug disorder, and one in four deaths results from illicit drug use. People suffering from drug and alcohol addiction also have a higher risk of unintentional injuries, accidents and domestic violence incidents.

Effects of Drug Abuse on Health

Substance use disorders are associated with a wide range of short- and long-term impacts on the user’s health. They can vary depending on the type of drug, how much and how often it’s taken and the person’s general health. Overall, the effects of drug abuse and dependence can be far-reaching. They can impact almost every organ in the human body. 

Side effects may include:

  • A weakened immune system, increasing the risk of illness and infection
  • Heart conditions ranging from abnormal heart rates to heart attacks and collapsed veins and blood vessel infection from injected drugs
  • Nausea and abdominal pain, which can also lead to changes in appetite and weight loss
  • Increased strain on the liver, which puts the person at risk of significant liver damage or liver failure
  • Seizures, stroke, mental confusion and brain damage
  • Lung disease
  • Problems with memory, attention and decision-making, which make daily living more difficult
  • Global effects of drugs on the body, such as breast development in men and increases in body temperature, which can lead to other health problems

The most severe health consequences of drug abuse is death. Deaths related to synthetic opioids and heroin have seen the greatest rise. In the past 12 months, 212,000 people age 12 or older have used heroin for the first time. Ever day, more than 90 Americans die after overdosing on opioids. 

Effects of Drug Abuse on The Brain

All drugs – nicotine, cocaine, marijuana, alcohol, and others – affect the brains “reward” circuit, which is part of the limbic system. This area of the brain affects instinct and mood. Drugs target this system, causing large amounts of dopamine, a neurotransmitter that helps regulate our emotions, motivation and feelings of pleasure, to flood the brain and produce a “high”.  

Although the initial drug use may be voluntary, drugs can change the chemistry of the brain. This affects a person’s self-control and interfere with their ability to resist intense urges to take drugs.  This leads to intense cravings and compulsive drug use. Eventually the behavior can turn into a substance dependency, or drug addiction. 

As a person continues to use drugs, the brain adapts by reducing the ability of cells in the brain’s reward center to respond to it. This reduces the high that the person feels compared to the high they felt when first taking the drug. They might take more of the drug to try and achieve the same high. These brain adaptations often lead to the person becoming less and less able to get pleasure from other things they once enjoyed, such as food, sex, or social activities.

Effects of Drug Abuse on Behavior

Substance abuse can lead to multiple behavioral problems, both short-and long-term, including:

  • Paranoia
  • Aggressiveness
  • Hallucinations
  • Addiction
  • Impaired Judgement
  • Impulsiveness
  • Loss of Self-control

These behaviors have serious consequences, like missed work, punishable offenses, accidents and injuries. In fact, drugs and alcohol are partly to blame for an estimated 80% of offenses leading to jail time in the United States. These incidents involve domestic violence, driving while intoxicated, and offenses related to damaged property. Legal and illegal drugs excluding alcohol are involved in about 16% of motor vehicle crashes. In the past year, almost 12 million people drove under the influence of illicit drugs, and almost 4,000 fatally injured drivers tested positive for drug involvement. 

Effects of Drug abuse on Unborn Babies

Illicit drug use poses great risks for pregnant women and their babies. Drugs may contain impurities that can be harmful to an unborn baby. Pregnant women who use drugs may be more likely to harm the fetus with risky behaviors and poor nutrition. Drug use can lead to premature birth or low birth weight. It can also cause the baby to have withdrawal symptoms (sometimes in the form of Neonatal Abstinence Syndrome), birth defects, or learning and behavioral problems later in life. Many substances pass easily through the placenta, so drugs that a pregnant woman takes also reach the fetus. 

Neonatal Abstinence Syndrome

Regular use of some drugs can cause Neonatal Abstinence Syndrome (NAS), in which the baby goes through withdrawal upon birth. Most research in this area focuses on the effects of opioids (prescription and heroin). However, the use of alcohol, barbiturates, benzodiazepines, and caffeine during pregnancy may also cause the infant to show withdrawal symptoms. The type and severity of withdrawal symptoms depends on the drugs used, how long and how often the birth mother used, how her body breaks down the drug, and whether the infant was born full term or prematurely.

Symptoms of Drug Withdrawal in Newborns

Symptoms of drug withdrawal in a newborn can develop immediately after birth or up to 14 days after and can include:

  • Blotchy skin coloring
  • Diarrhea
  • Excessive or high-pitched crying
  • Abnormal sucking reflex
  • Fever
  • Hyperactive reflexes
  • Increased muscles tone
  • Irritability
  • Poor feeding
  • Rapid breathing
  • Seizures
  • Sleep problems
  • Slow weight gain
  • Stuffy nose and sneezing
  • Sweating
  • Trembling
  • Vomiting

Long-Term Effects on the Newborn

Effect of using some drugs could be long-term and possibly fatal to the baby:

  • Birth defects
  • Low birth weight
  •  Premature birth
  • Small head circumference
  • Sudden Infant Death Syndrome (SIDS)

Risks of Stillbirth from Substance Use in Pregnancy

  • Tobacco use – 1.8 to 2.8 times greater risk of stillbirth, with the highest risk found among the heaviest smokers
  • Marijuana use – 2.3 times greater risk of stillbirth
  • Evidence of any stimulant or prescription pain reliever use – 2.2 times greater risk of stillbirth
  • Passive exposure to tobacco – 2.1 times greater risk of stillbirth

Can drug addiction be cured or prevented?

As with most chronics diseases, drug addiction is treatable and can be successfully managed. People who are recovering from an addiction will be at risk for relapse for years and possible for their whole lives. Research shows that combining addiction treatment medicines with behavioral therapy ensures that best chances of success for patients. Treatment plan tailored for each patient’s drug use habits and any occurring medical, mental, and social problems can lead to continued recovery. 

Long-Term Effects

Long-term drug use changes other chemical systems in the brain, affecting functions that include: 

  • Learning
  • Judgement
  • Decision-making
  • Stress
  • Memory
  • Behavior

Why do some people become addicted to drugs while others do not?

There is no one factor that predicts if a person will become addicted to drugs. It is a combination of factors that influence their risk for addiction. The more risk factors a person has, the greater the change that taking drugs that can lead to addition. 

  • Biology (Genetic) – The genes a person is born with account for about half of a person’s risk for addiction. Gender, ethnicity, and the presence of the mental health problems may also influence the risk for drug use and addiction.
  • Environment – A person’s environment includes influences from their family and friends to economic status and general quality of life. Outside factors such as peer pressure, physical abuse, emotional abuse, sexual abuse, early exposure to drugs, stress, and parental guidance can greatly affect a person’s likelihood of drug use and addiction. 
  • Development – Genetic and environmental factors influence critical developmental stages in a person’s life to affect addiction risk. Although taking drugs at any age can lead to addiction, the earlier that drug use begins, the more likely it will progress to addiction. This is particularly problematic for teens. The areas in their brains that control decision-making, judgement, and self-control are still developing. Teens may be especially prone to risky behaviors, including trying drugs. 

Commonly Abused Drugs

  • Alcohol
  • Cocaine (powdered)
  • Crack Cocaine
  • Heroin
  • Fentanyl
  • Prescription Opioids (Percocet, Vicodin, Dilaudid, OxyContin, Ultram, Roxicodone)
  • Suboxone
  •  Sedative-Hypnotics (Xanax, Ambien, Ativan, Klonopin, Soma, Valium)
  • Methamphetamine (powder and crystals)
  • Prescription Stimulants (Adderall, Ritalin, Vyvanse)
  • Ecstasy
  • MDMA (Molly)
  • Hallucinogens (LSD, Psilocybin (Magic Mushrooms))
  • PCP
  • Ketamine
  • Anabolic Steroids
  • Neurontin
  • Bath Salts (Synthetic Cathinones)
  • Kratom
  • Inhalants (duster, nitrous oxide)
  • Promethazine (cough syrup)
  • Marijuana 

Sources: Substance Abuse and Mental Health Services Administration and


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