The 12 Most Addictive Drugs

alcohol and pills on table
Alcohol and benzodiazepines are in the top 12 most addictive drugs.

Addiction affects millions of lives in the U.S. It is a chronic, progressive and relapsing disease that is characterized by compulsive drug-seeking behaviors and substance abuse, despite the harmful consequences that accompany it.

It’s hard for addicts to verbalize their feelings in general. Drugs can smother true emotions and, in many cases, that promise of avoidance is appealing. Instead of dealing with painful news or intense heartache, it’s often easier to escape reality by turning to mind-altering substances.

The disease carries with it a certain shame-laden stigma, making it much more than a “sensitive” subject. And for many, using problematic labels—particularly the word addict—can make the possibility of healing feel limited by language.

Let’s get down to the root cause and figure out what makes a person addicted to or dependent upon a substance. Since drugs physically change the brain’s structure, addiction is considered a “brain disease,” but it also creates numerous physical complications.

While there are a multitude of dangerous substances in circulation let’s take a look at 12 drugs that routinely lead to addiction & negative complications for the user.


Amphetamines are a central nervous system (CNS) stimulant, giving users a burst of “energy” or excitability. These drugs cause the release of chemicals called catecholamines, particularly dopamine. The effects are strong, producing pleasure sensations in the brain’s “reward pathway” and contributing to the addictive quality of amphetamines.1

Tolerance builds rapidly, requiring addicts to constantly increase their dosage, which brings on psychotic episodes.


Benzodiazepines such as Valium and Xanax are widely prescribed to treat anxiety, insomnia, alcohol withdrawal and other conditions.2 Though they work well for their intended uses, benzos are highly addictive and extremely difficult to kick.

The National Institute on Drug Abuse (NIDA) established that benzodiazepines have a short half-life, causing abusers to develop a quick and dangerous tolerance – often in as little as six weeks.3 Once a person becomes addicted, the drug causes rebound symptoms of the disorder it was originally prescribed for. Weaning off benzos is a very long and detailed process.


Methadone is a highly potent synthetic opiate that blocks the effects of heroin and other prescription drugs containing opiates. Methadone is approved for the treatment of heroin addiction, but is often considered more addictive than heroin and even harder to withdraw from.

Methadone’s strong effects on the CNS can cause it to be frequently abused in an attempt to “get high.” A methadone addict experiences the same opiate withdrawal symptoms, combined with strong cravings and compulsive use of the drug, despite the negative consequences.4


GHB (gamma hydroxybutyrate) is a CNS depressant. It was approved by the FDA in 2002 for the singular use of treating narcolepsy. Though it initially causes feelings of relaxation and euphoria, high doses of GHB can induce sleep, coma or death. Repeated use leads to GHB addiction and, ultimately, withdrawal symptoms like insomnia, anxiety, tremors and sweating.5


Scientific data shows that tobacco use is the leading preventable cause of disease, disability and death in the United States. An astounding 16 million people suffer with a serious illness that is caused by smoking.6

Nicotine acts in the same way that most addictive drugs do, by mimicking an acetylcholine receptor in the brain, while reducing the number of receptors that the brain produces. For many, the long-term brain changes caused by continued nicotine exposure result in addiction.7


Though legal, alcohol acts as a CNS depressant, meaning it relaxes, reduces anxiety and loosens inhibitions. When someone consumes alcohol, the brain releases dopamine and endorphins, which produce feelings of satisfaction and eliminate pain.8 Over time, people need to consume more and more alcohol in order to satisfy the brain.

Research has identified differences in how the reward center of the brain responds to alcohol in heavy and light drinkers. In either group, alcohol caused the release of naturally occurring feel-good endorphins in the two brain regions linked to reward processing. Once addicted, alcohol withdrawal presents dangerous physical and psychological issues.9


Cocaine is a stimulant drug that causes dangerous physical effects such as rapid heart rate and increased blood pressure. Cocaine is extremely addictive due to its short half-life and method of action. It keeps a steady stream of dopamine in the brain while users are high, preventing further dopamine production and closing down dopamine receptors. When withdrawal sets in, the brain starts to crave the lost dopamine the drug once provided, making it extremely hard to recover from.10


Made from a mixture of baking soda and powder cocaine, crack is a version of cocaine—but at a lower purity level. The key difference is that crack is smoked. This method of ingestion allows the drug to seep into lung tissues, producing a completely different result. Smoking crack causes the high to be much faster and more intense than the high traditionally felt from powder cocaine. Crack’s high is extremely short, usually less than 15 minutes, causing the user to crave a frightening amount of the drug. Withdrawal symptoms can cause immense depression, agitation and insomnia – all of which drive an addict to keep using the drug.11

Crystal Meth

Like cocaine, crystal meth acts on the dopamine level in the brain but provides an additional touch of mimicking norepinephrine. The result? Neurons release more of both, while training your brain to need more in order to survive. The hangover and withdrawals last days and can break down a person mentally and physically. Addicts suffer psychosis, hallucinations, memory loss, severe depression and sometimes suicide.12


Heroin is generally considered the most addictive drug in the world. Studies have shown that just one dose of heroin can put a person on the fast track to addiction. It’s estimated that nearly 25% of all people who try heroin at least one time will become addicted. Heroin causes euphoria, eases pain and numbs the brain and body by acting on an area of nerve cells within the central part of the brain known as the nucleus accumbens. When repeatedly subjected to this flood of opiates, the dopamine receptors within these nerve cells become exhausted from overstimulation.13

Another huge issue related to heroin addiction is the route of administration. A recent study found that addiction rates among heroin users varied depending on the mode of use they employed, showing that addicts who inject heroin have higher rates of dependence than those who smoked the drug.14


MDMA, also known as ecstasy or Molly, is a synthetic, psychoactive drug that affects three neurotransmitter systems in the brain: serotonin, dopamine and norepinephrine. Though there aren’t a large number of studies focused on MDMA dependency, those that have been conducted clearly illustrate the addictive nature of the drug.15

Lab rats have demonstrated that MDMA damages serotonin-containing neurons, and sometimes the damage is long-lasting.16 MDMA addicts experience a rapidly increasing tolerance and withdrawal symptoms such as fatigue, loss of appetite, depression and an inability to concentrate.


OxyContin, the brand name for oxycodone, is a potent synthetic opiate. Similar to heroin, OxyContin produces a euphoric high that is caused by stimulation of the brain’s reward center. OxyContin elevates levels of dopamine, the pleasure chemical of the brain.17

People intent on abuse discovered that crushing OxyContin tablets allowed them to inject or snort the drug, producing an intense high similar to that of heroin. Crushing the drug also eliminated the time-release mechanism of the tablets, greatly increasing the risk of addiction. And a recent study found that OxyContin is a gateway drug for heroin, which addicts may prefer as a less-expensive alternative to OxyContin.18


1. Center for Substance Abuse Research. (2013). Amphetamines.
2. National Institute on Drug Abuse. (2014). Prescription Drug Abuse: What are CNS depressants?
3. National Institute on Drug Abuse. (2012). Well-Known Mechanism Underlies Benzodiazepines’ Addictive Properties.
4. Medline Plus. (2016). Methadone.
5. Center for Substance Abuse Research. (2013). GHB.
6. Centers for Disease Control and Prevention. (2016). Smoking & Tobacco Use: Fast Facts.
7. NIDA for Teens. (2016). How Does Nicotine Act in the Brain?
8. National Institute on Drug Abuse. (2014). Alcohol.
9. Mitchell, J.M., O’Neil, J.P., Janabi, M., Marks, S.M., Jagust, W.J., Fields, H.L. (2012). Alcohol Consumption Induces Endogenous Opioid Release in the Human Orbitofrontal Cortex and Nucleus Accumbens. Science Translational Medicine, 116(4), 116.
10. National Institute on Drug Abuse. (2010). What is cocaine?
11. Center for Substance Abuse Research. (2013). Crack Cocaine.
12. National Institute on Drug Abuse. (2014). DrugFacts: Methamphetamine.
13. National Institute on Drug Abuse. (2014). Heroin: What is heroin and how is it used?
14. Gossop, M., Griffiths, P., Powis, B., Strang, J. (2006). Severity of dependence and route of administration of heroin, cocaine and amphetamines. British Journal of Addiction, 87(11), 1527-1536.
15. National Institute on Drug Abuse. (2006). MDMA (Ecstasy) Abuse: What is MDMA?
16. Simantov, R. (2003). Multiple molecular and neuropharmacological effects of MDMA (Ecstasy).
17. U.S. Food and Drug Administration. (2010). OxyContin – Questions and Answers.
18. Ameritox. (2014). A Deadly Trend: Prescription Drugs to Heroin.