The Top 15 Most Dangerous Drugs

Drug overdoses have been the leading cause of accidental death in the United States. In fact, more Americans die of drug overdoses than in car accidents each year. The Centers for Disease Control and Prevention (CDC) published a report that reviewed the drugs and drug mixtures most frequently involved in overdose deaths. Among drug overdose deaths during 2011–2016, the 10 most frequently mentioned drugs included Fentanyl, Heroin, Hydrocodone, Methadone, Morphine, Oxycodone, Cocaine, Methamphetamine, Alprazolam, and Diazepam. Although not mentioned in the CDC report, alcohol makes its way on the list of most dangerous substances as excessive alcohol consumption is the third leading preventable cause of death in the US. Nicotine, Synthetic Cannabinoids, MDMA, and Ketamine are also listed due to their dangerous health effects and risk of abuse.  

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The substances on this list span well-known prescription medications, infamous street drugs, and lethal combinations of both. Some of these prescription drugs are generally considered to be safe when taken on their own and under the correct conditions. However, all drugs can be fatal when too much is taken or combined inappropriately with other substances. If you or someone you know is abusing any type of drug, get in touch with a treatment provider here for information on finding help.

Here are the top 15:

1. Alcohol

Alcohol includes all types of beer, wine, and liquor. Alcohol ranks number one on this list due to its accessibility and the extensive health problems and injuries associated with use. An estimated 95,000 people die from alcohol-related causes annually.

“Although most people who consume alcohol do not meet the definition of addiction, many are not aware of the harmful effects it can have on the body and its organs.”

- Ashish Bhatt, MD, Doctor of Addiction Medicine

In addition to causing health issues such as cancer, liver damage, hypertension, heart disease, and fetal damage, alcohol abuse increases the risk of suicide, violence, and motor accidents. Moreover, alcohol withdrawal can be deadly, so it is never advised to detox from alcohol without medical supervision. If an individual begins to experience withdrawal symptoms when they are not using alcohol, treatment options may need to be considered. 

2. Fentanyl

Fentanyl, a Synthetic Opioid 100 times stronger than Morphine, is a significant contributor to fatal and nonfatal overdoses in the US. Drug dealers sometimes mix drugs with illicit Fentanyl to increase profits, often unbeknownst to the buyer. Cutting pills with Fentanyl is especially dangerous as an individual may take a substance more potent than they anticipated, and its high potency increases the risk of overdose. Over 150 people die daily from overdoses related to Synthetic Opioids like Fentanyl. There is no “safe amount” of illicit Fentanyl. If someone is using Fentanyl at all, contact a treatment provider today for treatment options because their life and health are on the line.

“Fentanyl is an extremely potent synthetic opioid. It is 50 times more potent than heroin and 100 times more potent than morphine and can be deadly even in trace amounts.”

- Ashish Bhatt, MD, Doctor of Addiction Medicine

3. Heroin

Heroin is an illicit Opioid made from Morphine. Typically injected or snorted, this dangerous drug is available as either a white or brown powder, or as a black and sticky substance known as Black Tar HeroinSerious health complications in users include collapsed veins, damaged tissue, infected heart lining, and more. According to the CDC, the number of Heroin users has more than doubled; approximately 80% of new users are coming to Heroin after having abused prescription Opioids. Due to Heroin’s high potency and high risk of addiction, recreational use of the substance can quickly turn into dependency, with withdrawal beginning after roughly 6 to 12 hours. Other significant dangers of Heroin use include overdose, increased risk of contracting infectious diseases, and permanent damage to the lungs, liver, kidneys, and brain. With the rising number of Opioid overdose deaths, there is no amount of Heroin that is without risk; find treatment options today. 

4. Hydrocodone

Like other prescription Opioid medications, Hydrocodone use presents a high risk for dependency, abuse, and addiction. With continued use of Hydrocodone, the body can become accustomed to the substance (known as tolerance), and in order to achieve the desired effect, the body will require higher doses. Taking higher and higher doses of Hydrocodone increases one’s risk of overdose, and within a few minutes of someone overdosing on Hydrocodone, they may stop breathing entirely. Other dangers of Hydrocodone abuse include impaired cognitive and motor function, slowed heart rate, and an increased risk of liver and kidney disease. It may be difficult to spot when someone is abusing prescription medications like Hydrocodone, but if an individual is using Hydrocodone beyond its intended means, treatment options are available.

5. Methadone

Methadone, a Synthetic Opioid, is commonly used as a drug substitute in the treatment of Morphine and Heroin addiction. While Methadone lessens the painful symptoms of Opiate withdrawal and blocks the effects of Opiates, the drug was still frequently referenced in overdose deaths between 2011 and 2016, according to the CDC. As a central nervous system depressant, if Methadone is used with other depressants, like alcohol or Benzodiazepines, the combined substances can cause dangerously low blood pressure and respiratory depression. If an individual is using Methadone beyond its intended means or taking a more significant amount than recommended by a doctor, this increases their risk of addiction and unintentional overdose. In that case, treatment options may need to be considered for Methadone abuse.

6. Morphine

Morphine is prescribed to treat severe pain, and it belongs to a class of drugs known as Opioid analgesics. According to the CDC, studies have shown that even 3 days of Opioid treatment can increase the likelihood of chronic Opioid use. Drinking alcohol, taking prescription or nonprescription medications that contain alcohol, or using street drugs while using Morphine increases the risk that an individual will experience severe breathing problems, overdose, and potential death. Like other Opioid-based medications, Morphine carries a high risk for abuse and addiction even when used as prescribed. If someone is showing warning signs of Morphine addiction, it may be time to consider treatment options.  

7. Oxycodone

Although Oxycodone (also known by the brand name OxyContin) is a prescription Painkiller that offers much-needed relief to those with severe pain or terminal conditions, the dangers of Oxycodone recreational use, misuse, and abuse can be severe and life-threatening. Taking Oxycodone in high doses or in combination with other substances (especially alcohol or other illicit drugs like Heroin or Cocaine) can result in respiratory distress, overdose, or even death. No amount of Oxycodone is safe enough for recreational use due to its high risk of addiction and dependence. It may be time to consider treatment for Oxycodone addiction if an individual is experiencing withdrawal symptoms, if they have difficulty stopping use, or if they begin to contemplate how much they could take before they overdose.

8. Cocaine

Cocaine, also known as “Blow,” “Coke,” and “Crack,” is a strong Stimulant that is used as a recreational drug. Cocaine use is associated with long-term health risks, including heart disease, hypertension, organ failure, respiratory distress, stroke, unhealthy weight loss, and seizures. According to the CDC, Cocaine deaths have been rising in recent years and show no sign of slowing down. Almost 20% of the overdose deaths that occurred in 2019 were linked to Cocaine. An individual should never cease Cocaine use abruptly or without medical supervision because dangerous and life-threatening withdrawal symptoms can occur. For those experiencing difficulty quitting Cocaine use, various therapies and support groups can help with treatment and long-term recovery.

9. Methamphetamines

Methamphetamines are highly addictive, synthetic Stimulants that affect one’s central nervous system and impact how the brain functions over time. During the CDC’s study period, the rate of drug overdose deaths involving Methamphetamine more than tripled. The dangers of Methamphetamine use include a multitude of long-term health effects, including psychosis, cardiovascular dysfunction, and an increased risk of infectious disease transmission. Even small amounts of Meth can have harmful health effects, as no quantity is safe or without any health risks. If an individual is having difficulty ceasing drug use or is contemplating how much of a substance one can take without overdosing, addiction treatment may need to be considered. 

10. Alprazolam (Xanax)

Alprazolam (Xanax), a highly potent Benzodiazepine, is often prescribed to treat insomnia and generalized anxiety disorders (GADs), but it can be highly addictive when used long-term. Benzodiazepines, like Xanax, are particularly dangerous because of their high prescription rates and increased risk of deadly respiratory depression (especially when mixed with other dangerous drugs). Recreational use of Xanax can cause multiple health risks, including delirium, cognitive impairment, increased risk of dementia, and psychosis. Often, those using Xanax begin to build a tolerance to the substance, which means they have to take a larger amount of Xanax to reach the same effect. Taking more than the prescribed amount of Xanax or using it in ways not recommended by a doctor is especially dangerous as it increases an individual’s risk of addiction and overdose. For recreational use, no amount of Xanax is safe or without any potential health risks, and an individual may need to consider treatment options if they begin to recognize any warning signs of Xanax addiction.

11. Diazepam (Valium)

Diazepam, commonly known by the brand name Valium, is a Benzodiazepine often prescribed to treat anxiety, muscle spasms, and seizures. Some underestimate the danger of Diazepam misuse due to its widespread availability, but long-term abuse of the substance can cause side effects like sleeping problems, hallucinations, anxiety, and life-threatening seizures. Additionally, Diazepam depresses the central nervous system, so it is dangerous to combine it with other substances that do the same, as it increases the risk of a fatal overdose. In fact, the CDC’s report found that other drugs were present in nearly all drug overdose deaths involving Diazepam. Using Diazepam, or any substance, recreationally is dangerous as everyone’s tolerance and reaction to the substance will vary, and one may need to consider treatment for Diazepam abuse if they are having difficulty ceasing use.

12. Nicotine

Nicotine is a highly addictive substance found in tobacco products. Despite widespread marketing campaigns for Nicotine-filled products, like e-cigarettes, the danger of Nicotine addiction and the harms of Nicotine have not lessened. The rising popularity of e-cigarettes over the recent years has increasingly placed young people at risk of developing a Nicotine addiction, with more than 2 million using vape pens in the US. Moreover, according to the CDC, smoking traditional cigarettes “is the leading preventable cause of death” in the US and “causes 90% of all lung cancer deaths.” Smoking tobacco harms nearly every organ in the body, can lead to premature death, and can increase the risk of stroke. The dangers of Nicotine use cannot be overstated, and treatment options are available for those looking to quit.

13. Synthetic Cannabinoids (K2/Spice)

Synthetic Cannabinoids, sometimes misleadingly called synthetic Marijuana or “fake weed,” contain lab-made, mind-altering chemicals similar to the chemicals present in the Marijuana plant. Although often marketed as safer than Marijuana, Synthetic Cannabinoids can produce dangerous, unpredictable, and even life-threatening effects. In fact, Synthetic Cannabinoids can affect one’s brain more intensely than Marijuana, leading to side effects like extreme anxiety, confusion, paranoia, and hallucinations. Additional severe mental and physical health problems caused by Synthetic Cannabinoids include vomiting, violent behavior, increased heart rate, and suicidal thoughts. Synthetic Cannabinoid products are often labeled “not safe for human consumption” and have a high potential for abuse. So, treatment options should be considered if an individual uses these substances.

14. MDMA (Ecstasy)

Initially popular in the nightclub scene, MDMA (also known as Ecstasy) is a synthetic drug that alters one’s mood and awareness of one’s surroundings. One specific danger of MDMA is that it is often cut with other substances, often unknown to the buyer, including Cocaine, LSD, Heroin, and Amphetamine. Anytime an individual takes multiple substances, the risk of overdosing increases substantially. MDMA use can also increase one’s heart rate to dangerous levels and cause a sharp rise in body temperature, which can lead to kidney failure and death. Because MDMA is an illicit substance, any use is considered abuse, and no amount can be deemed “safe” as continued use can lead to psychological or physical dependence. If an individual is using MDMA, treatment options are available.  

15. Ketamine

Ketamine is a dissociative drug used as an anesthetic in human and veterinary practice. Ketamine use can induce a feeling of almost complete detachment that is likened to a near-death experience. In high doses, Ketamine can cause serious health effects like delirium, impaired memory, impaired motor function, high blood pressure, and potentially fatal breathing problems. Using Ketamine recreationally is dangerous, and the risk of overdose significantly increases when Ketamine is used with other drugs like Opiates or Amphetamines. Seeking professional help is key to recovery from Ketamine addiction, and individuals can find treatment options here.

Even Common Drugs Are Deadly

The most dangerous drugs are not always the ones that people think of when they think about addiction. Unhealthy habits and problematic substance use can have slow, insidious harms that build up over time; users may find themselves in the thick of a severe health crisis without ever having seen a clear warning sign that they were headed there.

Even prescription medication, and perhaps especially prescription medication, can result in dependency and overdose. If you or a loved one is worried about the effects of a substance, legal or illegal, or wants to learn healthier ways to cope with life’s stressors, there is help available. To learn about treatment centers nearby and get questions about recovery answered, contact a treatment provider today.

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Carmen McCrackin

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  • Carmen McCrackin earned a B.A. in Journalism from the University of Auburn and is a professional writer. Her passion for writing and educating others led her to a career in journalism with a focus on mental health and social justice topics. Her main mission is to be a platform for all voices and stories, and to provide tangible resources to those seeking recovery for themselves or loved ones.

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Reviewed by Doctor of Addiction Medicine

Photo of Dr. Ashish Bhatt Dr. Ashish Bhatt , MD

  • Dr. Ashish Bhatt, MD, MRO is an accomplished physician, addiction medicine specialist, and psychiatrist with over 20 years of medical and administrative leadership.

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