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Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Albert Einstein Medical Center

Last full review/revision Jun 2020| Content last modified Jun 2020

Cocaine is an addictive stimulant drug made from leaves of the coca plant.

  • Cocaine is a strong stimulant that increases alertness, causes euphoria, and makes people feel powerful.
  • High doses can cause serious, life-threatening disorders, such as a heart attack or stroke.
  • The diagnosis can be confirmed by urine tests.
  • Sedatives such as lorazepam given intravenously can relieve many symptoms.
  • People who stop using the drug must be closely supervised because they may be suicidal and they require much help to remain free of the drug.

(See also Drug Use and Abuse.)

Cocaine has effects similar to those of amphetamines. It may be snorted, injected directly into a vein, or heated and inhaled. When boiled with sodium bicarbonate, cocaine is converted into a freebase form called crack cocaine. Heating crack cocaine releases cocaine vapor that can be inhaled. Inhaling the vapor is usually referred to as smoking, but the crack is not actually burned. Crack cocaine acts almost as fast as cocaine injected intravenously.

Heavy regular users and people who inject the drug intravenously or smoke it are most likely to become dependent. Light occasional users and people who take the drug nasally or by mouth are less likely to become dependent.


Cocaine use causes both immediate and long-term symptoms.

Immediate effects

Cocaine produces a sense of extreme alertness, euphoria, and great power when it is injected intravenously or inhaled. These feelings are less intense when cocaine is snorted. Because cocaine’s effects may last only a short time, users may inject, smoke, or snort it every 15 to 30 minutes. Binges, often over several days, lead to exhaustion and a need for sleep.


High doses can impair judgment and cause tremors, extreme nervousness, seizures, hallucinations, insomnia, paranoid delusions, delirium, and violent behavior. People sweat profusely and the pupils are dilated. Very high doses can cause a life-threatening high body temperature (hyperthermia).

Cocaine overdose can be fatal. Cocaine increases blood pressure and heart rate, and heart rhythm may be disturbed (called arrhythmias). Cocaine narrows blood vessels. If it narrows blood vessels in the heart, people can have chest pain, a heart attack (even in healthy young athletes), or sudden death. Cocaine can also cause kidney failure, stroke, and lung problems including difficulty with breathing and coughing of blood ("crack lung").

Long-term effects

Long-term users may develop tolerance, requiring more and more of the drug to get the same effects. Long-term use may damage the tissue separating the two halves of the nose (septum), causing sores (ulcerations) that may require surgery. Heavy use may impair mental function, including attention and memory. Chronic use can also damage the heart, causing scarring and thickening of the heart muscle and eventually leading to heart failure. Cocaine may contain many fillers, adulterants, and contaminants, which, when injected, can cause complications such as infections.

If women use cocaine during pregnancy, the fetus is more likely to have problems leading to miscarriage.

Withdrawal symptoms

Withdrawal reactions (cocaine washout syndrome) include extreme fatigue, sleepiness, and depression—the opposite of the drug’s effects. Appetite is increased, and people have trouble concentrating. Suicidal urges emerge when people stop taking the drug.

Did You Know...

  • Using cocaine can cause sudden death.


  • A doctor's evaluation
  • Urine tests

Doctors usually base the diagnosis on symptoms in people known to have used cocaine. Urine testing can confirm evidence of the drug.


  • Sedatives for agitation, high blood pressure, or seizures
  • Psychotherapy (for addiction)

Emergency treatment

Cocaine is a very short-acting drug, so treatment of uncomfortable reactions is usually not necessary. People who are very agitated or delirious or who have seizures or high blood pressure are given benzodiazepines (sedatives), such as lorazepam, intravenously. If sedatives do not control blood pressure, doctors may give nitrates or other antihypertensive drugs intravenously. Doctors avoid antihypertensive drugs called beta-blockers because they can worsen the effect of cocaine on blood pressure. Hyperthermia should also be treated with cooling techniques, such as wetting and blowing air over the skin or using special cooling blankets.

Detoxification and rehabilitation

Stopping long-term cocaine use may require close supervision because people can become depressed and suicidal. Entering a hospital or a drug treatment center may be necessary. The most effective method of treating cocaine addiction is psychotherapy. Many self-help groups and cocaine hotlines are available to help people remain free of the drug.

Sometimes the mental health disorders common to cocaine addicts, such as depression, are treated with the appropriate drugs for those disorders.

More Information about Cocaine

  • Cocaine Anonymous World Services
  • Dual
  • NAMI: National Alliance on Mental Illness
  • National Institute on Drug Abuse: Cocaine

Drugs Mentioned In This Article

Generic Name Select Brand Names
sodium bicarbonate No US brand name
lorazepam ATIVAN

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