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Drugs & Health

What Is a Drug?

A drug can be…

  • A natural or synthetic substance used in the diagnosis, treatment or prevention of a disease or to relieve pain
  • A habit forming substance that produces a state of arousal, contentment, euphoria, and/or sleep-inducing properties
  • Addictive when used continuously or excessively, with possible withdrawal symptoms when drug use is stopped
  • Legal or illegal (little to do with its potential for addiction or harm)

How Do Drugs Affect the Brain?

When someone puts drugs into their body, they tap into the brain’s communication system and tamper with the way nerve cells normally send, receive, and process information.

Different drugs -because of their chemical structures-work differently. We know there are at least two ways drugs work in the brain: some imitate the brain’s natural chemical messengers, and others over-stimulate the “reward circuit” of the brain by flooding it with dopamine, a neurotransmitter that is present in parts of the brain that regulate feelings of pleasure. Drug use can lead to the release of such large quantities of dopamine that other activities no longer feel pleasurable. A person may feel flat, lifeless, and depressed, and may be unable to enjoy things that once felt good or made them happy. The person may need drugs just to bring dopamine levels up to normal.

What Is Addiction?

Addiction is a chronic, often relapsing brain disease that causes users to continue using a drug or drugs despite negative results. While initiating drug use is usually a conscious choice, changes to the brain associated with addiction can limit a person’s self-control and can strengthen the urge to use drugs.

Addiction can be treated with a combination of therapy and medications. Treatment works best when it is tailored to the individual and takes into account not only drug use, but other social, emotional, and health issues. Like other chronic diseases, addiction can recur. Relapse is not a sign of treatment failure but of the need to adjust and provide additional support.

Harms of Problematic Drug Use

The reasons people use drugs often depend on their particular social and cultural experiences. The harms associated with drug use vary and are based on a number of factors. Potential harms include:

  • Physical harms: HIV, hepatitis C, overdose, wounds, withdrawal, violence
  • Psychological harms: depression, isolation, stigma, psychosis
  • Social harms: relationship issues, isolation from community, stigma
  • Economic harms: loss of money, loss of job, loss of housing
  • Legal harms: incarceration, criminal record

Additional Resources

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