Among the drugs classified
as amphetamines are amphetamine, methamphetamine (speed, crystal),
and methylenedioxymethamphetamine (MDMA, Ecstasy, or Adam). Methamphetamine
is the most commonly used amphetamine in the United States. Use
of MDMA is growing in popularity. Amphetamines are usually taken
by mouth but can be snorted, smoked, or injected.
Amphetamines may be used
almost continuously or used intermittently. Some amphetamines are
not approved for medical use, and some are manufactured and used
Some amphetamine abusers
are depressed and seek the mood-elevating effects of these stimulants
to temporarily relieve the depression. Others tend to use them in
high energy activities, such as at dance parties. Amphetamines cause
the release of increased amounts of dopamine in the brain, which
is the likely cause of mood elevation. MDMA differs from the other
amphetamines, in that it interferes with the reuptake of serotonin
(one of the body's neurotransmitters) in the brain. Amphetamine
users frequently develop dependence.
alertness (reduce fatigue), heighten concentration, decrease appetite,
and enhance physical performance. They may induce a feeling of well-being, euphoria,
In addition to stimulating
the brain, amphetamines increase blood pressure and heart rate.
Heart attacks have occurred, even in healthy young athletes. Blood
pressure may become so high that a blood vessel in the brain ruptures,
causing a stroke. Complications are more likely when drugs such
as MDMA are used in warm rooms with little ventilation, when the
user is very active physically (for example, dancing fast), or when
the user sweats heavily and does not drink enough water to restore
People who habitually
use amphetamines rapidly develop tolerance as part of their dependence.
The amount used ultimately may exceed several hundred times
the original dose. Most people using very high doses may become psychotic, because
amphetamines can cause severe anxiety, paranoia, and a distorted sense
of reality. Psychotic reactions include auditory and visual hallucinations
(hearing and seeing things that are not there) and a feeling of
having unlimited power (omnipotence). Although these effects can
occur in any user, people with a mental health disorder, such as schizophrenia,
are more vulnerable to them.
Symptoms opposite to the
drug's effects occur when an amphetamine is suddenly discontinued.
A person dependent on amphetamines becomes tired or sleepy—an effect
that may last for 2 or 3 days after stopping the drug. Some people
are severely anxious and restless, and some, especially those with
a tendency toward depression, become depressed when they stop. They
may become suicidal but may lack the energy to attempt suicide for
Emergency treatment is
needed only rarely. A person experiencing delusions and hallucinations
may be given an antipsychotic drug, such as chlorpromazine, which
has a calming effect and relieves distress. However, an antipsychotic
drug may sharply lower blood pressure. Usually, reassurance and
a quiet, nonthreatening environment help a person to recover.
Treatment may be needed
to correct dehydration and other complications of use. Long-term
users may need to be hospitalized during drug withdrawal for observance
of suicidal behavior. Otherwise, no treatment is generally needed
for people experiencing withdrawal.
Last full review/revision February 2003