Stimulants are drugs such as cocaine, "crack," and amphetamines that can cause the heart to beat faster, and blood pressure and metabolism to increase. Stimulants often cause a person to be more talkative and anxious and to experience feelings of exhilaration. They are often used to increase alertness and relieve fatigue.
Although cocaine is quickly removed and almost completely metabolized, methamphetamine has a much longer duration of action. The longer presence of methamphetamine in the brain ultimately leads to prolonged stimulant effects.
Both stimulants cause an accumulation of the neurotransmitter dopamine in the brain. This excessive dopamine concentration appears to produce the stimulation and feelings of euphoria experienced by the user.
The short-term effects of cocaine include constricted blood vessels; dilated pupils; and increased temperature, heart rate, and blood pressure. In rare instances, sudden death can occur on the first use of cocaine or unexpectedly thereafter, usually because of disrupted heart rhythms.
Large amounts of cocaine intensify the high, but may also lead to bizarre, erratic, and violent behavior. Heavy users may experience tremors, vertigo, muscle twitches, or paranoia. Some cocaine users report feelings of restlessness, irritability, and anxiety. This may result in panic attacks or even full-blown paranoid psychosis, in which the individual loses touch with reality and hears sounds that aren't there (auditory hallucinations).
Different ways of using cocaine can produce different adverse effects. For example, regularly snorting cocaine can lead to swallowing problems, hoarseness, loss of the sense of smell, nosebleeds, and a chronically runny nose. Cocaine that is eaten can cause reduced blood flow, leading to bowel problems.
There is no hard and fast rule for how long a drug will be detectable in one's system. Generally, traces of these stimulants can be detected by standard urine testing methods several days after use. The exact length of time varies from person to person and from test to test. It can also depend on the amount of drug used.
Taken in combination, alcohol and cocaine are converted by the body to a substance called cocaethylene. Cocaethylene lasts longer in the brain and is more toxic than either drug alone. The mixture of cocaine and alcohol is the most common two-drug combination that results in drug-related death.
Cocaine, methamphetamine, and amphetamines are highly addictive. After trying stimulants, an individual may have difficulty predicting or controlling the extent to which he or she will continue to use the drug. The stimulant and addictive effects are thought to be primarily a result of the drugs' ability to inhibit the reabsorption of dopamine by nerve cells.
Many cocaine addicts report that they seek but fail to achieve as much pleasure as they did from their first experience, suggesting tolerance to some effects of cocaine. Some users increase their doses to intensify and prolong the euphoric effects. Users can also become more sensitive to cocaine's anesthetic and convulsant effects over time. This increased sensitivity may explain why some deaths occur after apparently low doses of cocaine.
Doctors advise pregnant women not to use any drugs because they could harm the growing fetus. Cocaine's direct impact on pregnant women and fetuses is still not completely known. Scientists are now finding that exposure to cocaine during fetal development may lead to subtle but significant deficits later in life, including deficits in some aspects of information processing and attention to tasks-abilities that are important for success in school.
Fetal exposure to methamphetamine also is a significant problem in the United States. At present, research indicates that methamphetamine abuse during pregnancy may result in increased rates of babies who weigh less than normal at birth, whether or not they are born prematurely. Methamphetamine use during pregnancy may also result in altered behaviors in newborns, such as increased stress and unusual cry patterns. Ongoing research continues to study the developmental progress of children exposed before birth to methamphetamine as they get older.
Many behavioral therapies are effective. These approaches are designed to help modify the patient's thinking, expectations, and behaviors and to increase skills in coping with various stresses in life. Methamphetamine and cocaine recovery support groups also appear to be effective additions to behavioral therapies. Currently, no medications are available to treat individuals who are addicted to stimulants.
NIDA distributes a five-part series of cocaine treatment guides Geared to drug treatment professionals, the manuals incorporate a variety of behavioral treatment regimens to meet the needs of patients.
When someone has a drug problem, it's not always easy to know what to do. If someone you know is using a stimulant, encourage him or her to talk to a parent, school guidance counselor, or another trusted adult. In addition, the Substance Abuse and Mental Health Services Administration (SAMHSA) has a toll-free phone number (1-800-662-4357) to help direct a caller to treatment available nearby. SAMHSA's web-based Substance Abuse Treatment Facility Locator presents information on treatment centers by state.
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