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Amphetamines

By

Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;


Rika O’Malley

, MD, Grand Strand Medical Center

Reviewed/Revised Dec 2022
VIEW PROFESSIONAL VERSION

Amphetamines are stimulant drugs that are used to treat certain medical conditions but are also subject to abuse.

Amphetamines include the drug amphetamine and its many variants such as methamphetamine (speed or crystal meth) and methylenedioxymethamphetamine (MDMA, Ecstasy, or Adam). Methamphetamine is the most commonly used amphetamine in the United States. Use of MDMA Methylenedioxymethamphetamine (MDMA) MDMA (3,4-methylenedioxymethamphetamine) is similar to an amphetamine but has both stimulant and hallucinogenic effects. (See also Amphetamines and Overview of Substance-Related Disorders.)... read more is growing in popularity. Amphetamines are usually taken by mouth but can be snorted, smoked, or injected.

Some amphetamine users are depressed and seek the mood-elevating effects of these stimulants to temporarily relieve the depression Depression Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to interfere with functioning. It may follow a recent... read more . Others use them during high-energy activities. Amphetamines cause more dopamine to be released in the brain. (Dopamine is a neurotransmitter, a substance that helps nerve cells communicate.) This effect is the likely cause of mood elevation. MDMA Methylenedioxymethamphetamine (MDMA) MDMA (3,4-methylenedioxymethamphetamine) is similar to an amphetamine but has both stimulant and hallucinogenic effects. (See also Amphetamines and Overview of Substance-Related Disorders.)... read more differs from other amphetamines in that it also interferes with the reuptake of serotonin (another neurotransmitter) in the brain. Amphetamine users frequently develop dependence, often referred to as a substance use disorder Substance Use Disorders Substance use disorders generally involve behavior patterns in which people continue to use a substance (for example, a recreational drug) despite having problems caused by its use. The substances... read more .

Did You Know...

  • High doses of amphetamines may raise body temperature to dangerous levels.

Symptoms of Amphetamine Use

Amphetamines use causes both immediate and long-term symptoms.

Immediate effects

The following are some immediate effects of amphetamine use:

  • Increased alertness

  • Reduced fatigue

  • Heightened concentration

  • Decreased appetite

  • Enhanced physical performance

Amphetamines may produce a feeling of well-being, euphoria, and loss of inhibitions. Also, people sweat profusely, and their pupils are dilated.

Binge usage (perhaps over several days) eventually causes extreme exhaustion and a need for sleep.

Overdose

Long-term effects

People who habitually use amphetamines rapidly develop tolerance as part of dependence. They need to use more and more to get the same effect. The amount ultimately used may be more than several times the original dose. Most people using very high doses over several days or weeks become confused and psychotic because amphetamines can cause severe anxiety, paranoia, and a distorted sense of reality.

Psychotic reactions include hearing and seeing things that are not there (auditory and visual hallucinations) and false beliefs (delusions), such as a feeling of having unlimited power (omnipotence) or of being persecuted (paranoia). Memory may be affected. Confusion, memory loss, and delusions may last for months. Although these effects can occur in any user, people with a mental health disorder, such as schizophrenia Schizophrenia and Related Disorders , are more vulnerable to them.

Methamphetamine users have a high rate of teeth grinding (bruxism) and severe tooth decay affecting numerous teeth. The causes include decreased salivation, corrosive substances in the smoke, and poor oral hygiene—called "meth mouth."

Withdrawal symptoms

When an amphetamine is suddenly stopped, symptoms vary. People dependent on amphetamines become tired or sleepy—an effect that may last for 2 or 3 days after stopping the drug. As a result, they are more likely to be injured.

Some people are extremely anxious and restless, and some, especially those with a tendency toward depression Depression Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to interfere with functioning. It may follow a recent... read more , become depressed when they stop. They may become suicidal but may lack the energy to attempt suicide for several days.

Diagnosis of Amphetamine Use

  • A doctor's evaluation

  • A history of amphetamine use

Doctors base the diagnosis on symptoms in people known to have taken amphetamines. If the diagnosis is unclear, urine tests may be done, but the test may not detect methamphetamine and methylphenidate (a stimulant drug related to amphetamines).

Treatment of Amphetamine Use

After an overdose, treatment may include

  • Observation and monitoring until the person is sober

  • Sedatives

  • Blood pressure–lowering medications

  • Cooling for hyperthermia (dangerously high body temperature)

  • Treatment for depression and suicidal tendencies during withdrawal period

  • Cognitive-behavioral therapy to prevent relapse

Benzodiazepines (a group of sedative medications), such as lorazepam, are given intravenously to people with severe symptoms such as high blood pressure, extreme agitation, or seizures.

Medications for high blood pressure, such as labetalol or hydralazine, are given intravenously if blood pressure remains high.

During drug withdrawal, long-term users may need to be hospitalized so that they can be observed for suicidal behavior. Antidepressants Medications for Treatment of Depression Several types of medications can be used to treat depression: Selective serotonin reuptake inhibitors (SSRIs) Norepinephrine-dopamine reuptake inhibitors, serotonin modulators, and serotonin-norepinephrine... read more may be given if depression persists. Otherwise, no treatment is generally needed for people experiencing withdrawal.

Cognitive-behavioral therapy (a form of psychotherapy) helps some people stay free of amphetamines.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • National Institute on Drug Abuse (NIDA): Methamphetamine-specific information from the federal agency that supports scientific research into drug use and its consequences and supplies information about commonly used drugs, research priorities and progress, clinical resources, and grant and funding opportunities.

  • Substance Abuse and Mental Health Services Administration (SAMHSA): US Department of Health agency that leads public health efforts to improve behavioral health and provides resources, including treatment locators, toll-free helplines, practitioner training tools, statistics, and publications on a variety of substance-related topics.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Adzenys, Adzenys XR, Dyanavel XR, Evekeo
Desoxyn
Adhansia XR, Aptensio XR, Concerta, Cotempla XR, Daytrana, Jornay, Metadate CD, Metadate ER, Methylin, QuilliChew ER, Quillivant XR, RELEXXII, Ritalin, Ritalin LA, Ritalin SR
Ativan, Loreev XR
Normodyne, Trandate
No brand name available
NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
VIEW PROFESSIONAL VERSION
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