Caffeine is a central nervous system stimulant. It's one of the most popular drugs in the world, consumed by up to 90% of people in the world in one form or another, but most commonly in beverage form. It is a naturally occurring substance found in plants like cocoa beans, tea leaves, coffee beans, and kola nuts.

Energy drinks are beverages which contain large doses of caffeine and other legal stimulants such as guarana and ginseng. The amount of caffeine in an energy drink can range from 6 milligrams to over 500 milligrams per serving. This compares to 34 milligrams in Coca-Cola and 54 milligrams in Mountain Dew. If a drink advertises no caffeine, the “energy” typically comes from guarana and other stimulants, very similar to caffeine or actually containing derivatives of caffeine.

• Caffeine content of drinks
• Energy Drinks and Health

Cocaine is an addictive stimulant drug made from the leaves of the coca plant. Although healthcare providers occasionally use it as a local anesthetic for medical purposes such as surgery, it is otherwise an illegal controlled substance. Cocaine is the second most trafficked illegal drug in the world.

Other names for cocaine include:

• Blow
• Coke
• Crack
• Rock
• Snow

Ecstasy (aka: disco biscuits, molly, E, X, XTC) is the name for MDMA (3-4 methylenedioxymethamphetamine). MDMA (and its close relation MDA) is classified as an enactogen- drugs that have stimulant, hallucinogenic and mood-improving qualities. It was originally developed as a diet aid. Before it was made illegal in 1985, it was used experimentally by mental health professionals in controlled settings to help people in couple's counseling. It began to be used illicitly in the late 1980s and early 1990s. Though ecstasy use still continues today, its use among all age groups has substantially decreased from 2014 until now.

Inhalants are breathable chemical vapors that produce mind-altering effects. People who use inhalants breathe in the fumes through their nose or mouth, usually by “sniffing,” “snorting,” “bagging,” or “huffing.” Inhalants fall into four categories:

• Nitrites: room odorizers, video head cleaner, leather cleaner, or liquid aromas.
• Gases: nitrous oxide, ether, chloroform, and gases from household products such as propane tanks, whipped cream dispensers (whippets) and butane lighters.
• Solvents: paint thinners, glues, correction fluid, lighter fluid, electronic contact cleaners, felt-tip marker fluid, dry cleaning fluid and gasoline.
• Aerosols: spray paints, hair or deodorant sprays, aerosol computer cleaning products and vegetable oil sprays.

Although the high that inhalants produce usually lasts just a few minutes, people often try to make it last by continuing to inhale again and again over several hours.

LSD (lysergic acid diethylamide) is the most widely used hallucinogenic drug. It is also known as acid, blotter, or dots. The effects of LSD are unpredictable and depend on the amount taken; the person's personality, mood, and expectation; and the situation in which the drug is used. Effects are usually felt within 30 to 40 minutes after taking the drug. The LSD experience is often called a "trip" and can last up to 12 hours.

Methamphetamine (meth, speed, chalk, ice, glass) is a highly addictive manufactured stimulant drug that affects the central nervous system. It's a white, odorless, bitter-tasting crystalline powder that easily dissolves in water or alcohol. The drug was originally developed early last century to be used in nasal decongestants and bronchial inhalers. Although most methamphetamine is produced in "superlabs" outside of the United States, it is sometimes made with inexpensive over-the-counter ingredients in small, illegal home labs. The process of making methamphetamine takes about 48 hours and can be dangerous. Heating the solution produces toxic fumes and carries the risk of explosion, possibly resulting in burns or other serious health implications, including death.

Psilocybin and psilocin are chemical compounds obtained from certain types of dried or fresh hallucinogenic mushrooms found in Mexico, Central America and the United States. These compounds have similar structure to lysergic acid diethylamide (LSD).

There are over 180 species of mushrooms that contain the chemicals psilocybin or psilocin. Like the peyote, hallucinogenic mushrooms have been used in native rites for centuries. Both psilocybin and psilocin can also be produced synthetically in the lab.

Opioids are a class of drug that comes from natural or synthetic ingredients found in the opium poppy plant. Opioids work to reduce and alleviate pain by activating nerve cells in the brain known as opioid receptors that stop pain signals from the brain to the body. Opioids include prescription pain medications and illegal drugs, both of which can become addictive.

Some examples of prescription opioids include morphine, codeine, oxycodone (Oxycontin, Percocet), hydrocodone (Vicodin), fentanyl, methadone, tramadol, and buprenorphine. Oftentimes, opioids are combined with other medications, such as acetaminophen, when prescribed. Illegal opioids include heroin and any prescription opioid that is sold to people without a prescription.

Other names for opioids include:

• Opiates
• Painkillers
• Narcotics
• Oxy
• Lean

Sources 

• Mayo Clinic
• Cleveland Clinic
• Johns Hopkins Medicine
• BWell Harm Reduction Page
• Prevent Overdose Rhode Island
• The Centers for Disease Control and Prevention
• National Institute on Drug Abuse

Alcohol GHB, rohypnol and ketamine have become known as "predatory" or "date rape" drugs because they are used to incapacitate someone for the purposes of committing a crime, often sexual assault. Most of these drugs are odorless and colorless and can easily be slipped into someone's drink. They can cause dizziness, disorientation, loss of inhibition and a loss of consciousness. They can also produce amnesia, causing a victim to be unclear of what, if any, crime was committed. These drugs are particularly dangerous when combined with alcohol, although alcohol alone is still the drug most commonly associated with sexual assault.