A Complete List of Illegal Drugs: A to Z

Understanding what illegal drugs are and how they work can help you connect with someone in need. Your knowledge and kindness could save a life.

Keep reading to learn about different types of illegal drugs, including prescription versions, that are commonly misused. 

Benzodiazepines

Benzodiazepines are prescription sedatives that relieve anxiety, soothe muscle spasms, and prevent seizures. When used per a doctor’s orders, these drugs are legal, but some people crush the drug and snort it to get high. 

Many people with heroin and cocaine addictions also abuse benzodiazepines.[2] Co-administering the drugs can boost a high while reducing unpleasant side effects. Addictions can develop in time. 

The following benzodiazepines are commonly abused:

Ativan 

Ativan contains lorazepam, a powerful benzodiazepine. Doctors use this medication to treat insomnia caused by anxiety or stress. 

Doctors are encouraged to prescribe Ativan only for short periods lasting no longer than four weeks. Extended use can lead to physical dependence and uncomfortable withdrawal symptoms, including seizures.[3]

People abuse Ativan for its sedating and euphoric effects. Common street names include benzos, downers, and nerve pills. High doses taken for long periods can be incredibly dangerous. Learn more about Ativan and its common side effects.

Halcion 

Halcion is a prescription benzodiazepine containing triazolam. Doctors use it for short periods (no longer than about 10 days) to treat insomnia. 

Most patients can’t get a prescription for supplies lasting longer than a month. People with long-lasting sleep problems often need more help than Halcion can provide.[4]

People abuse Halcion in concert with stimulants like cocaine or methamphetamine. Halcion helps them to sleep when their stimulants wear off. 

Street names for the drug include barbs, benzos, and blues. Long-term abuse can lead to severe health problems, including seizures, when people try to quit. Learn more about Halcion and its common side effects. 

Klonopin

Klonopin is a prescription benzodiazepine containing clonazepam. Doctors use Klonopin to treat seizures and panic disorder. Sometimes, people take the medication for long periods, even though researchers say its effectiveness after about nine weeks of therapy hasn’t been studied.[5] 

Like all other benzodiazepines, Klonopin can cause both physical dependence and abuse. Street names for the drug include downers, tranks, and yellows. 

People buy and abuse the drug for its sedative power and potential to cause euphoria. Learn more about Klonopin and its common side effects. 

Librium

Librium is a prescription benzodiazepine containing chlordiazepoxide. Doctors use it to treat anxiety disorders, alcohol withdrawal, and pre-surgery anxiety. 

Most people take the medication for periods lasting no longer than four months. Its effectiveness for longer treatment time frames hasn’t been proven.[6]

While Librium is considered a safe and effective medication, it can also spark drug abuse and addiction. Street names for the drug include barbs, benzos, and downers. 

Combining Librium with another depressant (like opioids) is particularly dangerous, as it can lead to life-threatening sedation.[6] Learn more about Librium and its common side effects. 

Valium 

Valium is a prescription benzodiazepine containing diazepam. Doctors use it to treat anxiety, alcohol withdrawal, and muscle spasms. Doctors may also use it to treat convulsive disorders. 

Valium is designed for short-term use, as efficacy when used for more than four months hasn’t been proven.[7]

Valium can cause physical dependence, and it’s also been associated with psychological dependence (or addiction). Street names for Valium include yellows, barbs, and tranks. 

Abusers often crush the pills and snort the powder. Doing so can lead to serious health problems. Learn more about Valium and its common side effects. 

Xanax

Xanax is a prescription benzodiazepine containing alprazolam. Doctors use this medication to treat anxiety and panic disorders. 

When used as described, this medication is safe and effective. Sometimes, doctors keep their patients on the medication for extended periods for symptom control.[8]

Since patients can fill large Xanax prescriptions, the drug is relatively easy to find in medicine cabinets and from dealers. Street names include Liquid X, tranks, and bars. 

Long-term abuse can lead to serious problems, including seizures, when people try to quit. Learn more about Xanax and its common side effects. 

Rohypnol 

Rohypnol is a benzodiazepine containing flunitrazepam. The drug is manufactured and sold legally outside the United States, but it’s not approved for medical use in America. 

Since the 1990s, people have purchased Rohypnol illegally and used it to treat uncomfortable stimulant side effects. It’s also been used as a date-rape drug.[9]

Rohypnol abusers typically swallow capsules whole, or they crush the pills and inhale the powder. Street names include roaches, roapies, ruffies, and forget-me pills. 

Ongoing abuse of Rohypnol can lead to serious side effects, including memory impairment and tremors. Learn more about Rohypnol and its common side effects. 

Cannabis

Cannabis comes from the dried flowers of the cannabis sativa plant. Illicit users smoke the plant matter, brew it into teas, or mix it into foods like brownies or cookies. 

Marijuana’s active ingredient, THC, is a mind-altering chemical that produces intoxication. However, the plant contains more than 500 other chemicals, including some that are very similar to THC.[10]

Street names for cannabis include the following:[10]

• Weed
• Herb
• Pot
• Grass
• Bud
• Ganja 
• Mary Jane

The U.S. Food and Drug Administration has approved some THC formulations to treat conditions like cancer-related nausea and neuropathic pain. Experts warn that street cannabis may contain contaminants and additional elements that could cause more harm than good, however.[11]

Long-term potential cannabis side effects include cognitive reductions, poor memory, and lower IQ.[12]

Depressants 

Depressants are legal and illegal substances that induce sleep, reduce anxiety, ease muscle spasms, and prevent seizures. People abuse them to get high, enhance intoxication caused by other drugs, or deal with unpleasant side effects caused by other drugs. Long-term abuse of these substances can lead to physical dependence and/or addiction.[13]

These are among the most commonly abused depressants: 

Barbiturates

Barbiturates are depressant drugs doctors use to treat conditions like anxiety, muscle spasms, and seizure disorders.[14] These medications are older than other depressants (like benzodiazepines), and they’re typically considered less safe. 

People can quickly develop physical dependence and tolerance to barbiturates. People often take larger and larger doses once tolerance develops, which can lead to overdose.[13]

Benzodiazepines 

Benzodiazepines are prescription medications that are prescribed as muscle relaxers, seizure solutions, and anti-anxiety therapies.[2] See the “Benzodiazepines” section on this page for more detailed information on these types of drugs. 

GHB (Gamma-Hydroxybutyrate) 

GHB is another name for the generic drug sodium oxybate. This substance is sold as the prescription medication Xyrem. Doctors use it to treat narcolepsy. 

Some people buy and use illicit forms of the drug for its euphoric and calming effects. Some people who abuse the drug also believe GHB can help them build muscles and lose weight.[15]

GHB became notorious in the 1990s as a date-rape drug. High doses produce sedation and memory loss, incapacitating victims quickly. However, modern users may use GHB willingly. Some even develop drug dependence and addictions due to their ongoing abuse. 

Quaaludes (Methaqualone)

Quaalude is a street name for the medication methaqualone. This sedative-hypnotic drug was used between the 1950s and 1970s to treat insomnia. It was removed from the market in 1983 due to its high abuse risk.[16] 

While Quaaludes aren’t made within the United States, people can buy the drug from overseas dealers. And some street dealers offer these medications to their clients. 

At high doses, this medication can cause seizures, slow breathing, and gastrointestinal symptoms. Those side effects are more pronounced when Quaaludes are combined with other drugs, like opioids or alcohol.[16]

Sedative-Hypnotics 

Sedative-hypnotics are prescription medications that calm the central nervous system. They’re prescribed to treat anxiety and insomnia. 

Researchers say that these medications aren’t safe for long-term use.[17] Quitting these drugs takes time, as people often need to taper their doses to avoid uncomfortable withdrawal symptoms. 

Common sedative-hypnotics include the following:

• Lunesta: Lunesta is the brand-name version of the drug eszopiclone. Doctors use it to treat insomnia that hasn’t responded to other therapies.[18]
• Ambien: Ambien is the brand-name version of the drug zolpidem. Doctors use it for short-term insomnia treatment. Quitting the drug abruptly can lead to withdrawal symptoms, so tapering under medical supervision is typically recommended.[19]
• Sonata: Sonata is the brand-name version of the drug zaleplon. Doctors use it for short-term insomnia treatments. It works quickly and can cause complex behaviors while people are sleeping (like driving). Sonata has been associated with both physical dependence and drug abuse.[20]

Hallucinogens 

Hallucinogens can come from plants (like mushrooms), or they can be synthetically produced in laboratories. 

All hallucinogens can spark perceptual distortions. People may see, hear, or feel things others cannot. And some hallucinogens can cause shifts in how people feel about themselves and the world around them.[21]

No medical use for hallucinogens is accepted within the United States.[21] All hallucinogenic drugs are illegal. These are the most commonly abused varieties: 

Ayahuasca 

Ayahuasca is an ancient psychedelic beverage made from an Amazonian vine. About 40 years ago, people in the United States discovered the drink and started incorporating it into shamanic rituals. Now, some claim it can help with everything from depression to addiction.[22]

A typical ayahuasca serving contains multiple psychedelic compounds that work on brain cells and the serotonin system. However, it’s hard to control the brew’s strength. Some people get far too much of the substance and experience severe health issues.[22]

DMT (N, N-Dimethyltryptamine)

N, N-Dimethyltryptamine (often shortened to DMT) is a hallucinogenic substance found in plants. When ingested, the substance creates intense but short psychedelic changes. Shamans in South America have used the drug for centuries, but it’s become popular in America more recently.[23]

DMT can be ingested, but it’s frequently injected for a stronger experience. People claim the substance helps them understand themselves clearly. However, injected DMT can cause severe cardiac problems, including death.[23]

Ecstasy 

Ecstasy is a slang term for 3,4-methylenedioxy-methamphetamine. Users sometimes call this drug MDMA or Molly. It’s a synthetic hallucinogen that alters both a user’s mood and perception.[24]

Ecstasy is sold in pill, powder, and tablet formats. At high doses, it can impact a user’s ability to regulate body temperature. Those episodes can lead to organ failure or death. Additionally, many ecstasy doses are contaminated with other drugs, including fentanyl, so users may have no idea what’s inside the pills they’re about to take.[24]

Ketamine

Ketamine is commercially produced as a powder or liquid, and it’s designed for veterinary use. Most of the ketamine sold and used in the illicit market is stolen from veterinary clinics or smuggled from Mexico. Users sniff the powder or mix it with drinks or injectable drugs.[25] 

Street names for ketamine include cat tranquilizer, cat valium, and super K. It causes intense hallucinogenic effects that last about an hour. At high doses, the drug can cause heart damage.[25]

LSD

Lysergic acid diethylamide (or LSD) is an illicit hallucinogen. Dealers make the drug as a liquid and infuse small bits of paper with the drug. Users let the paper dissolve into their mouths for a strong high.[26]

Street names for LSD include acid, dots, and mellow yellow. All LSD bought and sold in the United States comes from the illicit market, as there is no accepted medical use for this substance. At high doses, LSD can cause high body temperature, fast heartbeats, and shaking.[26]

Mescaline 

Mescaline, also known as peyote, is a hallucinogenic drug that comes from a spineless cactus. Some dealers synthesize artificial mescaline to sell to their clients. 

Peyote has been used by indigenous people in Mexico as part of religious rites. Modern users take them for their hallucinogenic properties.[27]

Mescaline has no approved medical use, and it’s associated with a high potential for abuse. People who abuse these drugs chew them, smoke them, or brew them into tea. At high doses, they can cause increased heart rate and blood pressure.[27]

PCP

PCP is also known as animal tranq, goon dust, peter pan, and trank. PCP was developed in the 1950s as an anesthetic, but doctors stopped using it because people became agitated and irrational.[28]

People abuse PCP by swallowing tablets, smoking the powder, or dipping cigarettes in the PCP liquid and smoking them. High doses can cause seizures and coma. Long-term use can cause depression and memory loss.[28]

Psilocybin 

Psilocybin is a hallucinogenic drug that comes from mushrooms. The drug is ingested as a tea or sprinkled into another food (like eggs). Street names for the drug include magic mushrooms or shrooms.[29]

Mushrooms can cause nausea, vomiting, and a lack of coordination. Some people develop panic reactions and psychotic-like episodes, especially at very high doses. Experts also say that long trips caused by psilocybin can lead to death.[29]

Inhalants 

Also referred to as volatile substances, inhalants are not technically illegal drugs. They are often found in common household products like glue, lighter fluid, paint, air fresheners, felt-tip markers, butane, nitrous oxide, refrigerator coolant, and cleaning fluids.[30]

These products are abused by sniffing, bagging (inhaling fumes that have been collected in a plastic or paper bag), or huffing (from a balloon or rag soaked with the chemical). 

These are a few common inhalant substances: 

Amyl Nitrate 

Amyl nitrate is a prescription medication for chest pain relief. Drugs sold as amyl nitrate are commonly called poppers. They’re packaged in small bottles and marketed as air fresheners, deodorizers, and solvents.[31]

Some use these drugs to enhance a sexual experience. Even one dose could cause serious problems. Amyl nitrate is very dangerous and can cause blood pressure drops, seizures, coma, and death.[31]

Isobutyl Nitrate

Isobutyl nitrate is an inhalant that causes immediate and significant intoxication. Users often say it’s similar to drinking a significant amount of alcohol. Some drugs sold as poppers contain isobutyl nitrate.[32]

Like other inhalants, isobutyl nitrate can cause significant changes in blood pressure and alertness. At high doses, these drugs can cause death. 

Nitrous Oxide

Nitrous oxide is a nonflammable gas used as an anesthetic, often in dental offices. Dealers can sell it in a small, popper-like canister for easy sniffing. Each dose can cause sedation, but at high doses, it can also cause euphoria.[33]

At high doses, nitrous oxide can cause respiratory depression, nausea, and vomiting. Doctors can combat these side effects by replacing the drug with pure oxygen. People abusing the drug at home will likely not have this solution available.[33]

Opioids 

Opioids are painkillers. Legal versions include prescription drugs like Vicodin and OxyContin, but illicit versions include heroin. These drugs are incredibly powerful. In 2021, about 80,411 people died from an opioid overdose in the U.S.[34]

Buprenorphine

Buprenorphine is a prescription medication doctors use to treat opioid use disorder (OUD). Buprenorphine is a weak opioid that latches to receptors used by drugs like heroin and Vicodin. The weak attachment means people with OUD don’t get high with their doses.[35]

People without OUD can get high on buprenorphine. It’s critical for people with a prescription to guard it carefully to keep others safe. Some buprenorphine formulations also include naloxone as an abuse deterrent, which can make it safer.[35]

Codeine 

Codeine is an opioid painkiller doctors use to treat moderate-to-severe pain. Sometimes, codeine is mixed with other substances and sold as cough syrups.[36] When used as directed, codeine is safe, but ongoing use can be dangerous. 

Like all opioids, codeine can cause significant respiratory depression at high doses. It’s possible for people to overdose on their drugs. Users may find it hard to quit misusing opioids like codeine, so professional treatment is often needed. 

Fentanyl 

Fentanyl is a synthetic opioid that’s up to 50 times stronger than heroin.[37] It’s easy to make in a laboratory, and dealers don’t need to make very much to create many doses they can sell. Buyers may have no idea that their drugs contain fentanyl until they overdose. 

Fentanyl is sold as a powder, but dealers can also press it into pills that look like legal painkillers. Dealers also put fentanyl in nasal sprays and candies. Since it’s odorless and colorless, it’s almost impossible to tell if a dose contains fentanyl.[37]

Due to its potency, fentanyl is very likely to lead to overdose, which can be fatal.

Hydrocodone 

Hydrocodone is a generic drug sold under the brand names Vicodin, Lorcet, and Lortab. Sometimes, dealers sell prescription drugs they’ve stolen from pharmacies and doctors’ offices. Other times, they buy pills from people with valid prescriptions. It’s rare for dealers to make this drug in illicit laboratories.[38]

Hydrocodone is unsafe at high doses. It’s especially dangerous for people to take high doses of hydrocodone mixed with acetaminophen, as this substance can be harmful to organs like the liver.[38]

Hydromorphone 

Hydromorphone is a generic prescription painkiller that’s about eight times as powerful as morphine. It works quickly, so users value it for the powerful high they can get with just one dose.[39]

Street names for hydromorphone include dillies, juice, and smack. Users typically swallow their pills, but they can also crush their pills and snort or inject them. At high doses, hydromorphone can cause overdose, which can be fatal.[39]

Methadone

Methadone is a powerful medication doctors use to treat OUD. It’s more powerful than substances like buprenorphine, so it’s typically administered in appointments. People seldom take the drug for at-home use.[40]

People with OUD rarely get high on methadone. Instead, they feel fewer symptoms and drug cravings. People without OUD can develop a high when they take methadone. 

Morphine

Morphine is a narcotic derived from poppy plants. Most of the morphine in the United States is pressed into codeine or manipulated into other painkillers. However, some dealers sell morphine in a pure form.[41]

Street names for morphine include dreamer, morpho, and unkie. Brand-name drugs that include morphine include RMS, Roxanol, and MS-Contin. At high doses, this drug can cause overdose and death.[41]

Oxycodone

Oxycodone is a narcotic medication that’s traditionally been popular among the drug-using population. Street names for the drug include hillbilly heroin, kicker, and oxy. Brand names include OxyContin, Percocet, and Percodan.[42]

At high doses, oxycodone can cause extreme drowsiness, leading to life-threatening coma. People take the drug for euphoria and relaxation, and they may not realize they’ve taken too much until it’s too late.[42] 

Tramadol

Tramadol is a prescription painkiller designed for moderate-to-severe pain. It’s sold as a pill that either releases all the power at once or in an extended-release format. Some users crush and snort their pills to get a bigger high.[43]

At high doses, tramadol can cause an overdose. People may seem just relaxed or sleepy, but their breathing rates may slow so much that not enough oxygen gets to brain cells. Without quick action, these episodes can cause death. 

Steroids 

Anabolic steroids are synthetic drugs that are commonly abused to enhance athletic or physical performance, improve muscle growth, and boost physical appearance. Street names include Arnolds, gym candy, and pumpers. 

Steroids can be taken orally, injected intramuscularly, or applied directly to the skin. People who abuse them typically take 10 to 100 times the approved medical dose. At high doses like this, people can experience permanent physical changes, heart disease, and high cholesterol levels.[44] 

Stimulants 

Stimulants are substances that speed up the body’s systems. They’re sold as pills, powder, rocks, and injectable liquids. Users lean on these drugs because they produce a sudden rush of euphoria, followed by intense focus and an increased sense of energy.[45]

These are common stimulants people abuse: 

Amphetamines 

Amphetamines are prescription medications doctors use to treat ADHD and narcolepsy. When taken as directed, these medications are safe. However, these drugs have also been associated with heart conditions. 

Doctors are encouraged to monitor their patients while they are taking amphetamines. People who abuse these drugs won’t have medical supervision while they are taking them.[46]

Common prescription amphetamines include the following:

• Adderall: Adderall is the brand name of amphetamine salts. Several doses exist, and they’re all sold in pill form. 
• Concerta: Concerta is the brand name of methylphenidate. Several doses exist, and they’re all sold as pills. 
• Ritalin: Ritalin is another brand name for methylphenidate. Extended-release forms deliver a small amount of active ingredient for long periods. 
• Vyvanse: Vyvanse is the brand name for lisdexamfetamine. This medication comes in pill form in an immediate-release format. 

Cocaine 

Cocaine is a stimulant drug that originates from the coca plant in South America. Doctors can use cocaine in very limited ways. For example, they might use it as a local anesthesia for eye surgeries. However, most powdered cocaine is made in illicit labs.[47]

People use powdered cocaine by snorting the powder or rubbing it onto their gums. Others dissolve the powdered cocaine and inject it. Cocaine moves quickly into the brain cells and causes euphoria.[47]

Crack 

Crack is a manipulated form of cocaine. Dealers add ingredients to powdered cocaine to make a glass-like substance that can be heated up and inhaled. The drug makes a cracking sound when heated, which gives the drug its name.[47]

Crack comes with the same risks powdered versions do, including intense addictions and the potential for overdose. People can overdose and die on crack the very first time they use it.[47]

Methamphetamine 

Methamphetamine is a very powerful stimulant drug that works directly on the central nervous system. People can abuse meth by smoking it, swallowing a pill, snorting powder, or injecting powder dissolved in water.[48] 

Even small amounts of meth can cause irregular heartbeats, increased blood pressure, and high body temperature. These episodes can be life-threatening. Continued use can lead to intense addictions that are difficult to overcome.[48]