Negative Health Effects of Various Illegal Drugs

Many illicit drug users 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

Young teenagers smoking marijuana which contains THC
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Proponents of marijuana legalization and pot smokers, in general, tend to believe there is no harm in using marijuana, but scientific research tells us differently. 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 four times the deposition of tar compared to cigarette smoking and more carcinogens, including 50 percent more benzoprene and 75 percent more benzanthracene.


Effects of Methamphetamine

Man Smoking Meth

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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 chronic users. After a relatively short period of use, methamphetamine will begin to show on the faces of some users and begin to rot their teeth, known as "meth mouth."

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

cocaine lines

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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, long-term 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 amphetamines and cocaine users.

MDMA can cause a long list of psychological and physical problems, which range from sleep disruption to severe anxiety, from nausea to blurred vision and from increased heart rate to high blood pressure. But the main danger with ecstasy use is that it is often mixed with other drugs, which can have unexpected consequences.


The Health Effects of Heroin

Cooking up Heroin, UK

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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. Users 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 just a few hours 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 person's decision-making, behavioral control, and stress management.


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: A regular user of LSD 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

There is a reason that drugs are illegal. Mainly, it is because research has found that they can be dangerous in the short term and harmful to your health in the long run. Using illicit drugs is putting at risk your life, health, and the ability to #liveverywell.

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.

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