Stimulants and depressants are drugs that alter natural function of the brain. As a result, they can affect people's feelings and actions profoundly. Generally, stimulants intensify mental and physical functions, such as alertness and heart rate. Depressants have a relaxing effect and might slow physical functions, such as breathing. Stimulants and depressants come in forms of food components, prescription medicines and illicit drugs. Like many other classes of drugs that affect the brain, many stimulants and depressants are addictive and may have serious side effects.
Stimulants are chemicals that elevate mood, alertness and energy. They may help maintain mental focus, intensify concentration, augment energy and reduce appetite. In addition, stimulants affect the body by increasing blood pressure, temperature, and heart and breathing rates. Some stimulants improve breathing by expanding the main airways of the lungs.
Doctors prescribe stimulants to treat attention deficit hyperactivity disorder and narcolepsy, a chronic brain disorder that causes extreme daytime sleepiness. Stimulants are sometimes prescribed for limited, short-term use in people with obesity, but only when other therapies have failed.
Commonly used stimulants include:
-- Nonprescription: caffeine, nicotine.
-- Prescription medications: dextroamphetamine (Dexedrine, Adderall), methylphenidate (Ritalin, Concerta), modafinil (Provigil, Nuvigil).
-- Street drugs: 3,4-methylenedioxymethamphetamine (MDMA, "Molly," "ecstasy"), methamphetamine (crystal meth), cocaine.
Depressants slow activity of the brain and body. They are used medically to help control anxiety, sleeplessness and seizures. They also reduce heart and breathing rates, blood pressure, muscle tension and pain. The muscle relaxation and sedation these drugs cause make them useful during certain medical procedures. In modern, fast-paced society, many people rely on depressants as sleep aids. Approximately 4 percent of U.S. adults use prescription sleep medications, according to the Centers for Disease Control and Prevention.
Commonly used depressants include:
-- Nonprescription: alcohol.
-- Prescription medications: diazepam (Valium, Diastat), alprazolam (Xanax), zolpidem (Ambien, Edluar, Intermezzo), carisoprodol (Soma), pentobarbital.
-- Street drugs: flunitrazepam (Rohypnol, "ruffies"), gamma-hydroxybutyrate (GHB).
Addiction and Abuse Potential
Tolerance, physical dependence and addiction potential often accompany extended use of stimulants or depressants. Tolerance refers to needing greater doses of the drug to get the same effect. With physical dependence, the drug has to be taken regularly to avoid symptoms of withdrawal. Tolerance, dependence and addiction can lead to drug abuse. Both illicit and prescription drugs can be abused.
The Substance Abuse and Mental Health Services Administration reports that among the U.S. population aged 12 and older in 2013, 1.3 percent used prescription stimulants for nonmedical purposes, while 2.2 percent used depressants for nonmedical reasons. According to an August 2013 article in the "Annals of Internal Medicine," 30 percent of U.S. population misuses alcohol.
Warnings and Precautions
Because stimulants and depressants may negatively affect health and well-being, these drugs must be used exactly as recommended by a doctor. Using high doses of these drugs, mixing them simultaneously, and combining stimulants or depressants with other drugs or alcohol increase the risk for side effects, such as panic attacks, hallucinations, paranoia, hostile behavior, depression, and sleep and appetite problems.
Some side effects of stimulants and/or depressants require immediate medical attention, including:
-- Shortness of breath, chest pain, dizziness or fainting.
-- Hearing and believing things that are not real.
-- Profuse sweating with chills.
-- Swelling of the tongue or throat, and trouble breathing.
-- Seizures or loss of consciousness.
If you notice these or other changes in the way you feel while taking a stimulant or depressant, talk with your doctor right away. Do not stop taking your medication unless your doctor tells you to do so. These medications often have to be stopped gradually, which must be supervised by a medical professional.
- American Journal of Psychiatry: Blood Pressure and Heart Rate in the Multimodal Treatment of Attention Deficit/Hyperactivity Disorder Study Over 10 Years
- National Institute on Drug Abuse: How Do Stimulants Affect the Brain and Body?
- Centers for Disease Control and Prevention: Prescription Sleep Aid Use Among Adults: United States, 2005–2010
- Substance Abuse and Mental Health Services Administration: Results From the 2013 National Survey on Drug Use and Health: Detailed Tables
- Annals of Internal Medicine: Screening and Behavioral Counseling Interventions in Primary Care to Reduce Alcohol Misuse: U.S. Preventive Services Task Force Recommendation Statement
- Pharmacological Reviews: Psychostimulants and Cognition: A Continuum of Behavioral and Cognitive Activation
- Drug and Alcohol Dependence: Adverse Effects of Stimulant Drugs in a Community Sample of Drug Users
- U.S. Food and Drug Administration: FDA Asks Attention-Deficit Hyperactivity Disorder (ADHD) Drug Manufacturers to Develop Patient Medication Guides