The 10 Worst Drugs to Abuse: 10 Drugs You Definitely Want to Avoid

All addictive substances have the potential to ruin a life. Even cannabis/marijuana can trap people in the same cycle of addiction. However, some drugs are worse than others. Some are simply lethal due to their potency; others have side effects so powerful even one use of these Blog Post "The 5 Most Dangerous Drugs", published dangerous drugs can have lifetime effects. Sometimes, the worst drugs to abuse are even sold as other drugs.

Finally, a few of the 10 worst drugs to abuse are even legal.

The 10 Worst: Our List of the Worst Drugs to Abuse

One of the best things a person concerned about substance abuse can do is get informed about the dangers of substance abuse. Although addiction always ends the same way, it's important to know some drugs are definitely worse than others. These drugs are either very addictive, capable of severely damaging a life, very potent...or all of the above.

So, here's our list of the 10 worst drugs to abuse.

#1: Fentanyl

Fentanyl is infamous for its potency – the drug is 50 times more potent than heroin. This synthetic opioid painkiller has legitimate uses – it helps people deal with severe chronic pain. However, much of the fentanyl found on the street is produced in clandestine, illegal drug labs. Fentanyl creates a sense of euphoria and is highly addictive; it can also cause respiratory depression, coma, and death from overdose.

Why is fentanyl one of the 10 worst drugs to abuse? Opioid abuse is very dangerous. Here’s an example: In California, there were nearly 7,000 opioid-related deaths in 2021. Nearly 6,000 were related to fentanyl. Fentanyl is often sold as other drugs and contaminates drug stashes because it’s used to cut other drugs.

#2: Carfentanil

Carfentanil may be the most potent opioid drug in the world. According to the U.S. Department of Justice, carfentanil is 10,000 times more powerful than morphine, and 100 times as potent as fentanyl. Originally created as a tranquilizer for large animals like elephants, carfentanil started being responsible for drug overdoses last decade.

Like fentanyl, carfentanil often contaminates drug stashes, making it easy to ingest and fatally overdose. That alone makes carfentanil one of the 10 worst drugs to abuse.

Learn more about the dangers of Carfentanil addiction.

#3: Alcohol

According to the Centers for Disease Control & Prevention, excessive alcohol use kills 140,000 Americans each year via alcohol overdose and more. The deaths range from chronic diseases like cancer and cirrhosis brought on by heavy drinking, to assaults, accidents, poisonings, and falls. It’s easily one of the 10 worst drugs to abuse. It’s also legal in all 50 states.

Alcohol is a depressant, meaning it slows down the functions of the central nervous system. Alcohol abuse leads to blackouts, impaired judgment, and aggressive behavior. The drug has also been linked to an increased risk of certain types of cancer.

In 2020 alone, alcohol-related diseases killed more than double the number of people who died from drug overdoses. That’s why it’s important to recognize that alcohol is one of the 10 worst drugs to abuse – and can be just as dangerous as illegal ones.

#4: Methamphetamines

This illegal, incredibly powerful, and highly addictive stimulant has ruined countless lives. Its infamous physical effects (like “meth mouth”) are well-known, and meth abuse can cause serious, permanent damage to the heart, brain, and other organs. Meth also has severe mental effects, including paranoia, psychosis, hallucinations, and violent behavior.

This alone makes methamphetamine one of the 10 worst drugs. But meth’s dangers seem to be evolving. P2P meth is a newer formulation of meth found on the streets that appears to be even more intense. This so-called “new meth” appears to be far stronger and capable of producing intense, long-lasting psychosis in users.

#5: Heroin

Heroin is an incredibly addictive narcotic that’s derived from morphine. One of the most infamous illegal substances, heroin has had a long and sad presence throughout history. Heroin’s physical effects can be devastating, including collapsed veins, liver and kidney disease, and increased risk of HIV and hepatitis infection due to sharing needles.

There are also mental health risks associated with heroin use – users often suffer severe depression and losses in cognitive function, leading to a downward spiral that’s hard to break out of. For these reasons, heroin is one of the 10 worst drugs to abuse.

In addition, heroin addiction has been linked to higher rates of opioid overdoses due to its strength and related uncertainty in how potent each batch may be. Also, fentanyl is often used to cut heroin batches, meaning users may not be expecting the extreme potency of fentanyl. The risk of fatal overdose makes this drug especially dangerous.

#6: Inhalants

It may be surprising to read that many common household items -- cleaners, paint, glue, and so on -- can be used as a way to get high by sniffing their fumes. Although not very well understood, inhalant abuse continues to trap many people in addiction. In 2021, the Substance Abuse and Mental Health Services Administration's (SAMHSA) annual National Survey on Drug Use and Health found nearly 335,000 people had an inhalant use disorder. Inhalants also include gases like nitrous oxide. Other common inhalants include:

• Amyl nitrite and butyl nitrite:

  Often sold as "video head cleaner" as a legal fig leaf, this class of inhalant has been known as "poppers" in certain subcultures.

• Benzene:

  Found in gasoline, benzene fumes can cause leukemia over time.

• Freon:

  used in refrigerators and air conditioning systems, freon can also cause cold injuries when sniffed.

• Nitrous oxide:

  Known as laughing gas, nitrous oxide can cause death due to oxygen loss in the brain. Safe when given by a trained medical professional, nitrous oxide can also cause blackouts.

• Toluene:

  Used in nail polish, cleaners, and many other products, this solvent causes brain and organ damage when used over time.

Inhalants are one of the 10 worst drugs to abuse for one very clear reason: many of the household products used in inhalant abuse weren't intended for human consumption. There are multiple health risks that come from inhaling fumes, some of which result in death. Inhalants cause extensive damage across the human body. Even gases like nitrous oxide which have legitimate medical uses can cause inexperienced users to suffocate.

Finally, inhalants are often used by teens and preteens as a way to experiment with drug use.

#7: Synthetic Cannabinoids

This is a large, ever-changing class of drugs often sold semi-legally as "liquid incense" or "potpourri." Named because they're chemically similar to the active ingredient in cannabis (or marijuana), these chemicals are commonly known as K2, spice, fake weed, and synthetic marijuana, among many other names. Researchers class these chemicals as "new psychoactive substances," which also include the infamous "bath salts" drug.

First developed as research chemicals to study the effects of marijuana, synthetic cannabinoids are often advertised as a safe alternative to cannabis. In reality, synthetic cannabinoids are much, much stronger than marijuana, with unpredictable (and sometimes fatal) side effects. This unpredictability is why synthetic cannabinoids are one of the 10 worst drugs to abuse.

#8: Benzodiazepines

Benzodiazepines are a class of prescription tranquilizers used to treat anxiety and sleep disorders. They're also used as sedatives. Prescribed under the brand names Ativan, Klonopin, Valium, Xanax, and more, these drugs are generally safe to use as prescribed.

When abused, however, it's a different story. Benzos are highly addictive, especially when abused. Prescription drug abuse is a major gateway to addiction for thousands of Americans. Just because a drug has a prescription label doesn't mean it's safe or nonaddictive. Drug abuse includes:

• Taking someone else's prescription

• Recreationally using prescription drugs

• Taking more of a prescription drug than was prescribed

• Mixing prescription drugs with other drugs (benzos and alcohol can cause blackouts; it can also result in a fatal overdose)

• Continuing to use a prescription drug after the prescription ends

Benzos can cause feelings of euphoria, which drives their abuse. Benzo addiction is treatable, but it can be a difficult process. This combination of availability and risk is why benzodiazepines are on our list of the 10 worst drugs to abuse.

#9: Oxycodone

Sold as OxyContin and Roxicodone, this prescription opioid was portrayed as a literal miracle drug when it was first marketed heavily in the 1990s. Unfortunately, overprescription and overuse of this opioid painkiller opened up a pathway to opioid addiction for tens of thousands of Americans. One of the most recreationally used drugs in the United States, oxycodone has been a driver of the opioid epidemic for years.

A genuine gateway drug, we're counting oxycodone as one of the 10 worst drugs to abuse simply because it's trapped so many people in the cycle of abuse.

#10: Cocaine

Cocaine is an illicit stimulant that's highly addictive. Most often consumed in powder form by snorting (inhaling), cocaine can also be injected and smoked in a crystalized form known as crack cocaine.

Although the drug has had a glamorous cachet for a long time, cocaine is as deadly as every other drug on this list. According to the Centers for Disease Control and Prevention, deaths involving cocaine significantly rose in 2021. The violence and exploitation around cocaine's manufacture and sale also earn it a spot on our 10 worst drugs to abuse list.

If Your Drug Isn't One of the 10 Worst Drugs to Abuse, It Doesn't Mean It's Safe

Ultimately, any addictive drug will damage a person's life. Our list of the 10 worst drugs to abuse simply lists 10 drugs we've found to be the worst of the worst. Even casual drug use can damage your life, and any use of illicit drugs carries a significant risk of physical and mental addiction. If you or someone you know is struggling with substance abuse, speak to staff at a drug rehab or other treatment professional right away. Don't wait until the situation escalates beyond your control. Addiction treatment helps many people each year.

The effects of drug addiction can be catastrophic, but with the right help, healing is possible. We encourage anyone battling an addiction to reach out and get help before it's too late. Together, we can make a difference in our society and work hard towards a better tomorrow. The 10 worst drugs to abuse should serve as a reminder that substance abuse carries a serious risk, and we should all be informed and aware of the consequences.

With proper guidance and support, you can beat addiction and start living a healthier life.

Struggling With Drugs? The Forge Recovery Center Can Help

If you're finding yourself trapped by one of the 10 worst drugs to abuse or any other addictive substance, The Forge Recovery Center can help. Our outpatient drug rehab will give you the tools you need to leave substance abuse behind and help you build a life without drug and alcohol addiction. We'll start by helping you find a drug detox center near you and help you through the entire recovery process.

When you enter our care, you'll join a welcoming community of care, with staff acting as your companions on your journey to recovery. You'll participate in effective, evidence-based treatment and even enjoy regular fun adventures on the weekend.

Don't risk a drug overdose! Contact The Forge Recovery Center today and start your journey away from addiction.

Frequently Asked Questions

What is drug abuse?

Drug abuse is the deliberate and excessive use of drugs to achieve the desired effect. It can include recreational drug use, misuse of prescription medications, or intentional overdose of any psychoactive substance.

How do I know if I'm addicted to drugs?

You may be addicted to drugs if you find yourself using them more often than intended, having difficulty controlling your drug use, or noticing that the effects of the drug are increasingly wearing off. If you think you might be addicted to drugs or are concerned about a friend's behavior, speak to The Forge Recovery Center today for advice and support.

What happens if addiction is untreated?

If addiction is untreated, it can lead to severe consequences such as physical and mental health problems, financial instability, trouble in relationships, and even death. It's important to get help if you think you might be addicted to drugs so your situation doesn't escalate beyond your control.

What are the long-term effects of drug abuse?

The long-term effects of drug abuse will vary depending on the substance abused. Generally, however, drug abuse can lead to permanent changes in brain chemistry and increase the risk of mental illness, heart disease, stroke, cancer, and even death. It's important to seek help right away if you think you or someone you know might be addicted to drugs and alcohol.

Are all addictive drugs dangerous?

Yes, all addictive drugs are dangerous. Even casual drug use carries a risk of physical and mental addiction and can lead to severe consequences. If you or someone you know is struggling with substance abuse, speak to The Forge Recovery Center for help.

Written by

Brian Moore

Content Writer

Reviewed by

Jeremy Arzt

Chief Clinical Officer

February 11, 2023