Negative Health Effects of Various Illegal Drugs

Many people who use illicit drugs think that the only bad thing about doing drugs is that they are illegal and if you get caught, you can go to jail. The truth is there are negative health effects associated with every illegal drug out there and some of them can be fatal.

Here is a summary of the most commonly used illegal drugs and the effects each could have on your health.


The Health Effects of Marijuana

Close up of marijuana in mason jar

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Although marijuana has become legalized in many places in recent years, there are still potential health effects of using this substance. Studies have shown that smoking weed can have negative effects on the brain, the heart, and the lungs.

Although no link has been confirmed between smoking marijuana and the risk of developing cancer, marijuana smoking leads to the significant deposition of tar and carcinogens.


Effects of Methamphetamine

Bag of methamphetamine

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The health effects of methamphetamine use may be the most noticeable and visible of any of the commonly abused illegal drugs because it has such a dramatic effect on the outward appearance of people who chronically use the substance. After a relatively short period of use, methamphetamine will begin to show on the faces of some who use it and begin to rot their teeth.

Meth is a stimulant, which affects the body's central nervous system. It's highly addictive ​and cheaper than many other street drugs, which is why so many get hooked so easily.


The Health Effects of Cocaine

A person's hand holding a small bag of cocaine

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The effects of cocaine may not be as immediately noticeable as those of meth use, but they can be just as devastating. Although cocaine overdose is rare, the use of the drug can lead to an increased risk of heart attack and stroke. Cocaine stimulates the central nervous system and affects how the brain processes dopamine. Other health problems can occur depending on how the drug is used: snorted, ingested, or injected.


Health Effects of Ecstasy

Ecstasy pills

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Although MDMA (also called ecstasy) is a so-called designer drug, negative health effects associated with its use are similar to those experienced by people who use amphetamines and cocaine.

MDMA can cause a long list of physical problems, which can include sleep disruption, severe anxiety, nausea, blurred vision, increased heart rate, and high blood pressure. It can also lead to increased body temperature that can be fatal. Another danger of ecstasy use is that it is often mixed with other drugs, which can have unexpected consequences.


The Health Effects of Heroin

Heroin in powder form and in syringe

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Some of the health effects associated with heroin use are not due to the use of the drug itself but related to the manner in which it is used. People who inject heroin can suffer many negative health effects related to infections that develop due to the use of non-sterile injection techniques. It's easy to overdose on heroin, which is often cut with other toxic substances.

Heroin is a highly addictive drug in the opioid family, with withdrawal symptoms beginning shortly after the drug is taken. Studies have also found that heroin use can lead to a loss of the brain's white matter, which plays a role in a variety of important brain functions.


Effects of LSD

LSD tabs

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There are really very few studies about the long-term health consequences associated with the use of LSD. Most of the physical effects produced by LSD use are relatively mild; its psychological effects are much more dramatic.

The main problem with LSD use is that its effects are unpredictable: Someone who uses LSD regularly can suddenly experience an acute adverse reaction, including severe anxiety, paranoia, and panic attacks, known as a "bad trip," at any time.

A Word From Verywell

Research has found that these drugs can be dangerous in the short term and harmful to your health in the long run. Using illicit drugs means putting your health at risk. If you or a loved one are struggling with addiction, talk to a healthcare professional who can help provide you with the resources you need to recover.

If you or a loved one are struggling with substance use or addiction, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area.

For more mental health resources, see our National Helpline Database.

8 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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