What Are Drug Classifications?

Learn about the seven drug classifications, what they consist of, and the various ways drugs are categorized.

What Are Drug Classifications?

There are seven drug classes in the medical industry. Due to the many varying effects, purposes, and types, classifications are needed to help categorize and label the drugs. For example, hallucinogens make people experience things that aren’t real, while dissociative anesthetics change how the brain perceives pain. Narcotic analgesics relieve pain, too, but can also cause a euphoric, dreamlike state.

Each drug classification offers a distinct series of effects and includes subcategories. Explore each entry in greater detail below. 1
Drug Classifications


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CNS Depressants

Central nervous system (CNS) depressants are drugs that depress the central nervous system. This can be achieved through various methods, including:
  • Barbiturates, such as phenobarbital (Luminal) and mephobarbital (Mebaral)
  • Benzodiazepines, such as diazepam (Valium) and alprazolam (Xanax)
  • Non-benzodiazepine sedative hypnotics, such as zolpidem (Ambien) and eszopiclone (Lunesta)
  • Alcohol

CNS Stimulants

CNS stimulants are drugs that stimulate the central nervous system. They increase alertness and aggressiveness while enhancing attention span and potential cognitive capacity. Popular CNS stimulants include:

  • Cocaine
  • Amphetamines, such as Adderall
  • Methamphetamine (meth or “crank”)


Hallucinogens alter perceptions of reality. Examples include:
  • LSD
  • MDMA (ecstasy)
  • Mescaline

Dissociative Anesthetics

Dissociative anesthetics are drugs that temporarily alleviate the perception of pain. Some common dissociative anesthetic drugs include:
  • Phencyclidine (PCP)
  • Dextromethorphan (DXM)
  • Ketamine

Narcotic Analgesics

Narcotic analgesics are drugs that relieve pain and induce sleep. Drugs in this class also have a strong sedative effect, so they are often used to manage chronic pain. Some examples of narcotic analgesics are:
  • Opium
  • Morphine
  • Heroin
  • Hydrocodone
  • Codeine


Inhalants are a class of chemicals or substances used to produce a psychoactive effect. Inhalants can include:
  • Gasoline
  • Paint thinner
  • Paint
  • Toluene
  • Hair spray


Cannabis is a psychoactive drug used to produce euphoria but has been shown to have many other effects on the mind. Cannabis can be smoked, vaporized, or baked into food products.

How Are Drugs Classified?

Classifications are typically lumped into two categories of drugs: pharmaceutical drug classifications and addictive drug classifications. Take a moment to look over each category to discover its parameters.

Pharmaceutical Drug Classifications

These drugs are solely categorized for their ability to treat medical conditions. There are many pharmaceutical drug classifications, such as anti-inflammatories, antibiotics, immunological agents, hormone suppressants, inflammatory bowel disease agents, and ophthalmic agents.
Often, drugs under this classification can be obtained via a licensed medical professional, making them safe for consumption whilst intake is properly monitored. However, this classification of drugs can still be misused, sold and distributed illegally, and those who take these substances can still develop dependencies or negative side effects. It is important to rely on medical supervision when ingesting these substances.

Addictive Drug Classifications

These drugs have beneficial medicinal properties but have a high risk for abuse. Addictive drug classifications include methamphetamines, cocaine, and painkillers, such as Percocet, Norco, Vicodin, or OxyContin. When considering the implications of these drugs, it is important to consult a licensed medical professional.

Drugs Classification by Chemical

Drugs are diverse and created with a variety of chemicals to produce different effects.


Alcohol is the most commonly abused substance in the world, as it can be legally and, for the most part, easily obtained. Alcohol causes euphoric feelings while lowering inhibitions, causing severe impairment of judgment, reaction times, and perception.

Moreover, long-term consumption of this CNS depressant leads to severe liver damage, which can be fatal.


Benzodiazepines, or benzos, affect the gamma-aminobutyric acid (GABA) neurotransmitter, which is responsible for reducing neuronal stimulation. As such, the drug is prescribed for sleep and psychiatric conditions.

In 2019, 16% of overdose deaths were caused by benzodiazepines. Benzodiazepine is highly addictive and is therefore commonly abused. In addition, the withdrawal process can prove fatal due to the severe symptoms the body endures when ceasing use of this drug. 2


Cocaine is a stimulant drug—it increases the activity of certain neurotransmitters in the brain like dopamine, serotonin, and norepinephrine, leading to increased levels of arousal and alertness. It can also lead to increased blood pressure and heart rate.

If taken as prescribed by a doctor, cocaine can be used for medical purposes, such as a local anesthetic. Although there are medical benefits from using cocaine, it can be dangerous when abused since, when taken in high doses, it can lead to heart attacks or respiratory failure. Moreover, it is highly uncommon for doctors to use cocaine as a form of treatment.

Cannabis or Cannabinoids

Marijuana (cannabis) has become far less scrutinized in recent years and is even prescribed as an alternative to synthetic medicines in some states. Nevertheless, while cannabis and cannabinoids aren’t as addictive as other drug classes, they can cause serious health concerns, such as anxiety, suicidal ideations, and hyperemesis syndrome.


The opioid analgesics classification is a big topic right now. Opioid painkillers like Vicodin and OxyContin have a high risk of addiction and fatal overdoses. In 2019, over 70% of overdoses were caused by opioids. 3

These drugs were originally created to treat pain; however, they are highly addictive and must be prescribed with careful patient monitoring.


Barbiturates are highly addictive and have some of the highest overdose risks among the classifications of drugs listed here. At one time, this drug was commonly prescribed for a wide variety of symptoms, including sleep disorders.
Today, however, barbiturates are predominately prescribed to patients for conditions like epilepsy or as anesthesia. Barbiturate medications include Luminal and Amytal.

Drugs Classification by Effect

This section discusses each classification of drugs according to their action or effect. As you will see, the actions vary widely among the different entries.


Stimulants are classifications of drugs that block the reuptake neurotransmission of dopamine and norepinephrine. They lead to increased central nervous system activity and present a euphoric rush. Improper or prolonged use can lead to seizures or heart failure.

According to a survey conducted in 2006 by the Drug Abuse Warning Network (DAWN), of all drug-related emergency department visits, 31% involved cocaine, 5% involved methamphetamine, and 2% involved amphetamine. 4


Abusing hallucinogens causes altered or false perceptions of reality. This creates the inability to determine the accurate time, colors, motions, or sounds.


The opposite of stimulants, depressants impair the body’s central nervous system, causing drowsiness and calmness.


Inhalants can include hair spray, volatile solvents, lighter fluid, and more. The damaging effects of inhaling such substances puts the body at high risk of physical damage and even death.

Legal Classification of Drugs

The legal classification of drugs refers to the different regulations that govern the production, trade, and use of these substances. Drug scheduling is especially important in determining how these substances are treated under the law.
For instance, if a drug is classified as a Schedule I substance, the drug has a high potential for abuse, is not accepted for medical use, and lacks safety regulations. Thus, it is more difficult to obtain and more expensive than other substances. Nonetheless, not all drugs are classified as Schedule I substances, as seen below. 5

Detailed Classifications

  • Schedule V: Drugs in Schedule V have the lowest potential for abuse and addiction and include drugs, such as Lyrica and Motofen.
  • Schedule IV: Although there are penalties and regulations pertaining to Schedule IV drugs, they possess a lower potential for addiction and abuse. Such drugs include Darvocet and Ambien.
  • Schedule III: Authorities classify drugs like Vicodin and anabolic steroids under Schedule III. These drugs have clear medicinal benefits, but their potential for addiction and abuse is much higher than the Schedule IV group of medications.
  • Schedule II: These drugs have medicinal benefits, but they possess a much higher potential for abuse and addiction and carry a severe risk of dependence. These include methamphetamines, OxyContin (oxycodone), cocaine, Adderall, fentanyl, and others.
  • Schedule I: Schedule I drugs, such as heroin and LSD, are classified as having no accepted medicinal benefits and are highly addictive.

Treatment for Drug Addiction

Treatment for Drug Addiction

Fortunately, there are options available to treat drug addiction and dependency. Successful recovery is possible using the various methods below, allowing patients to reclaim their lives and achieve life-long sobriety.


During controlled detoxification, the patient receives medications to lessen the effects of withdrawal to provide as much comfort as possible while the drug is cleared from the body.

Residential Care

This is the most intensive level of care for substance abusers, usually lasting six months or more. Residential care provides a safe place for patients to receive treatment and equips them with essential life skills to overcome their addiction.

What’s more, each patient’s unique needs are met via a carefully constructed and tailored treatment program that takes place on-site.

Inpatient Care

Inpatient care consists of ongoing therapy at an on-site facility to aid the patient in a successful recovery.

Outpatient Care

As the least-invasive form of treatment, outpatient care provides the patient with tools to combat temptation in the real world. Outpatient care has proven to be a formidable line of defense against relapse.

Contact Concise Recovery to Learn More

Are you or your loved one struggling with an addiction? If you’re ready to get real, evidence-based help, contact Concise Recovery today. We offer comprehensive care solutions to meet your individual needs.