There are a lot of different types of drugs that are abused for a range of reasons. However, abuse is more common for some drugs than it is for others. This often has to do with how easy it is to get access to the drug type or how expensive it is.

Common addictions can either be to illicit drugs or to prescription medications, as well as to other materials that are not normally considered to be drugs but that are easy to access. Regardless of the type of drug or substance, addiction is a mental health disorder, which means that sometimes people will experiment with drugs across categories that provide the same type of physical and mental response.

Categories

 

Different drugs do different things to the brain and body, resulting in different sensations. People may be drawn to different drugs based on the physical reaction and mental sensations the drugs seem to cause. These categories, clarified by Villanova University, provide an overall umbrella for understanding the most common drugs that result in addiction.

Many of the most common addictions are to drugs that, in one way or other, affect the dopamine system, which regulates the body’s pleasure response. This is the reaction that results in the person feeling euphoric, or “high.” However, other systems can be involved, including natural brain chemistry that can make someone feel relaxed, create a sense of high energy or stimulation, or cause the person to experience visions and other sensations that are not real.

Central Nervous System (CNS) Depressants

CNS depressants are substances that cause a person to feel relaxed. These drugs are often used by those who are experiencing high stress or anxiety as a way to relax and feel calm and uninhibited. Some of the subcategories of CNS depressants include:

  • Sedatives
  • Opiates
  • Hypnotics
  • Anesthetics

These drugs generally work directly on the dopamine system to create a sense of calm, pleasure, and reward. However, another area they often affect is the gamma-aminobutyric acid (GABA) system, which slows down messages in the brain, helping to create that sense of calm.

CNS Stimulants

Stimulants do exactly what it sounds like: They have a stimulating effect that makes the person feel more alert, high-energy, and powerful. Along with affecting the dopamine system, these drugs can affect the body’s stress response system to encourage the production of neurochemicals that drive the fight-or-flight response, which causes the body to become more alert and active.

Unlike CNS depressants, these drugs speed up messages in the brain, causing the person to feel more energetic while at the same time driving focus. Stimulants also often have a side effect of decreased appetite, which can result in weight loss, making it more likely that someone who is concerned about appearance will abuse these drugs for weight loss, resulting in addiction.

Hallucinogens and Club Drugs

Some people use drugs to feel a psychedelic or depersonalized effect, seeing visions or feeling separated from the self. As noted by the Medline Plus encyclopedia, these types of drugs are often collectively referred to as “club drugs” because they are most likely to be encountered at clubs, raves, or similar parties. Because of the dissociative and hypnotic effects many of these drugs have, some may be used as a “rape drug” – slipped into someone’s drink or otherwise given without the person’s knowledge to cause a blackout, making the individual vulnerable to attack.

Hallucinogens are considered less likely to create a physical addiction because they do not necessarily affect the dopamine system. However, if the person uses the drug long enough, a psychological compulsion to use it can develop. One of the main symptoms of addiction is an uncontrollable compulsion to use the substance even when it causes harm. Physical dependence is not required for this reaction to occur.

Other Types of Drugs

Other drugs or substances sometimes have a combination of these actions. For example, marijuana can be both a stimulant and a relaxant. Some club drugs can provide a hypnotic effect while also inducing hallucinations.

In addition, there are also some legal medicines available over the counter that can, when abused, cause the person to develop a psychological addiction. As described by the Foundation for a Drug-Free World, over-the-counter cough syrup is often abused by young people who don’t have access to other types of substances. Sometimes, people will inhale non-drug substances such as paint for similar reasons. In some cases, repeated use can result in the person feeling compelled to keep using these substances, similar to what happens with hallucinogens.

Specific List of Most Common Addictions

 

The substances described below constitute the most common substances of abuse and addiction, including many described by the National Institute on Drug Abuse:

Illicit Drugs

addiction and economicsWhen most people think of addiction, they think either of alcohol or tobacco, or of illicit drugs that are controlled by the U.S. Drug Enforcement Agency. The most common illicit drugs of abuse include:

  • Heroin: CNS depressant made from the opium poppy
  • Cocaine: CNS stimulant made from the coca plant
  • Methamphetamine: high-potency CNS stimulant that results in severe physical symptoms
  • Ecstasy: club drug with stimulant and hallucinogenic properties
  • PCP: anesthetic used to create out-of-body experiences
  • LSD: hallucinogen
  • Mushrooms, peyote, DMT, and similar natural substances: hallucinogens
  • Ketamine: anesthetic that can cause hallucinations
  • Rohypnol: hypnotic and sedative club drug implicated in date rape situations
  • Marijuana: stimulant and hypnotic properties; most commonly used illegal drug

Prescription Medications

As described by WebMD, the legal and illicit drugs described above are considered by many to be the main addictive and dangerous substances of abuse or addiction. However, what is often left out of the equation is that prescription medications and some easy-to-purchase non-drug substances can also lead to addiction.

The Centers for Disease Control and Prevention have declared that the US is in the middle of a prescription drug abuse and overdose epidemic, which continues to lead to high numbers of overdose and death. The main substances involved in this include:

  • Narcotic pain relievers: natural or synthetic drugs that behave like opium in the body, such as OxyContin, Vicodin, Percocet, morphine, codeine, and others
  • Benzodiazepines: anti-anxiety medications like Xanax, Valium, Klonopin, and Ativan
  • ADHD medications: amphetamine-based and non-amphetamine stimulants, including Ritalin and Adderall, as well as a legal form of methamphetamine

Legal Addictive Substances

There are two legal substances that are well-known for their high addiction potential.

  • Alcohol: Wine, beer, and hard liquor all contain alcohol, a recreational substance that acts as a CNS depressant. While many people can consume this substance casually without developing addiction, others respond negatively to how alcohol affects the dopamine system, resulting in addiction.
  • The addictive component of tobacco, nicotine, is a stimulant. However, addiction to tobacco is often described by the individual as being relaxing. Theories about this include the idea that the repetitive motion and ritualistic aspects of smoking lead to addiction.