An Overview of Stimulants and How They're Used

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Stimulants are a class of psychoactive drug that increases activity in the brain. These drugs can temporarily elevate alertness, mood, and awareness. Some stimulant drugs are legal and widely used.

Many stimulants can also be addicting. Stimulants share many commonalities, but each has unique properties and mechanisms of action. Drugs that are classified as stimulants include:

  • Caffeine
  • Cocaine
  • Methamphetamine
  • Nicotine
  • Prescription stimulants


Caffeine is the most widely used psychoactive drug in the world, found in coffee, tea, cocoa, chocolate candy, and soft drinks. While caffeine has several positive effects such as increasing energy and mental alertness, heavy use can cause symptoms such as anxiety and insomnia.

Caffeine is physically addictive, and withdrawal symptoms can include headaches, fatigue, and irritability.


Nicotine is considered one of the three most widely used psychoactive drugs in the world despite the fact that there are few (if any) medical uses for the drug. During the early to mid-twentieth century, smoking was considered fashionable.

Reports of the adverse health consequences have led to cigarette use being increasingly shunned. However, the Centers for Disease Control and Prevention (CDC) reports that in 2014, approximately 17% of U.S. adults over the age of 18 (around 40 million individuals) smoke cigarettes.

The National Institute on Drug Abuse reports that tobacco use is a leading preventable cause of death, disease, and disability in the U.S., with cigarette use attributed to more than 480,000 premature deaths each year.

Nicotine is a primary ingredient in e-cigarettes, and vaping is highly addictive. Vaping nicotine has become an increasing problem among teens and young adults. According to the Centers for Disease Control and Prevention, more than 5.4 million youth in the United States were current e-cigarette users in 2019. 


Cocaine is an illegal psychoactive drug made from the leaves of the coca tree. During the late 1800s, psychoanalyst Sigmund Freud advocated the use of cocaine as a therapeutic treatment for psychological disorders, but later realized the addictive properties of the drug.

During the early 1900s, cocaine was legal in the U.S. and could be found in many over-the-counter medications. In 1906, the government began requiring manufacturers to label cocaine-containing products and began placing serious restrictions on distribution by the early 1920s.

Cocaine is a restricted substance and its use and sale are considered illegal in most cases. Today, cocaine is one of the most frequently used illegal drugs in the United States.

Cocaine is rapidly absorbed from any administration point, including being snorted, inhaled, injected or taken orally. The drug reaches the brain quickly and is then distributed to other tissues throughout the body. Cocaine is rapidly metabolized by enzymes in the liver and plasma in approximately 30 to 60 minutes but can be detected in urine tests for up to 12 hours after administration.


Methamphetamine, also known as meth, is extremely addictive and destroys tissues in the brain, which can lead to brain damage. In the 1950s and 1960s, methamphetamine was commonly prescribed for medical conditions including depression, narcolepsy, and obesity. 

In the 1960s, people began using the drug recreationally, although meth use waned in popularity until the 1980s. Today, a smokeable form of crystallized methamphetamine (d-methamphetamine hydrochloride) or crystal meth is popular.

The effects of methamphetamine, which can last from four to eight hours, begin rapidly after intravenous use or when it is smoked. Symptoms of meth withdrawal can occur 24 hours after you stop using meth, and can range from mild to severe, depending on the frequency of use and dependency.

Prescription Stimulants

Prescription stimulants are a group of psychoactive drugs that affect the central nervous system and the autonomic nervous system. Some of the effects of using these drugs include tremors, vasoconstriction, restlessness, tachycardia, insomnia, agitation and loss of appetite.

These agents were once widely used in obesity and weight loss treatments, but their addictive properties have caused them to be rarely used today for that purpose. Prescription stimulants are currently used to treat some physical and psychological disorders, including attention-deficit hyperactivity disorder (ADHD) and narcolepsy.

Common names of prescription stimulants include:

  • Ritalin (methylphenidate)
  • Adderall (dextroamphetamine-amphetamine)
  • Dexedrine (dextroamphetamine)

Prescription stimulants work by enhancing the effects of dopamine and norepinephrine and can lead to increased blood pressure, respiratory function, and euphoria.

8 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Kendra Cherry, MSEd
Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."