Cocaine


Coca Leaf
From the plant called Erythroxylon coca, cocaine is a local anesthetic and central nervous system stimulant. It can be taken by chewing on coca leaves, smoked, inhaled ("snorted") or injected.
Coca Plant

History of Cocaine

Early Spanish explorers noticed how the native people of South America were able to fight off fatigue by chewing on coca leaves. A medical account of the coca plant was published in 1569. In 1860, Albert Neiman isolated cocaine from the coca leaf and described the anesthetic action of the drug when it was put on his tongue. Angelo Mariani, in the early 1880s produced a "medicinal" wine, called Vin Mariani, that contained 11% alcohol and 6.5 mg of cocaine in every ounce. The famous psychotherapist, Sigmund Freud, in 1884, recommended cocaine for a variety of illnesses and for alcohol and morphine addictions. Unfortunately, many of his patients went on to become addicted to cocaine! In 1886, John Pemberton developed Coca Cola, a drink that contained cocaine and caffeine. Cocaine was REMOVED from Coca Cola in 1906 (but it still has the caffeine). The Harrison Narcotic Act in 1914 made cocaine illegal. Finally, in 1985, crack cocaine was introduced and rapidly became a major drug problem.

Coca Wine


Crack

Effects of Cocaine on the Nervous System

A dose of between 25 to 150 mg of cocaine is taken when it is inhaled. Within a few seconds to a few minutes after it is taken, cocaine can cause:
  • a feeling of euphoria
  • excitement
  • reduced hunger
  • a feeling of strength
After this "high" which lasts about one hour, users of cocaine may "crash" into a period of depression. This crash causes cocaine users to seek more cocaine to get out of this depression and results in addiction. Withdrawal from cocaine can cause the addict to feel depressed, anxious, and paranoid. The addict may then go into a period of exhaustion and they may sleep for a very long time.

Various doses of cocaine can also produce neurological and behavioral problems like:

  • dizziness
  • headache
  • movement problems
  • anxiety
  • insomnia
  • depression
  • hallucinations

Cocaine



Emergency Room Visits due to Cocaine and Heroin

Image courtesy of the Office of National Drug Control Policy

Death caused by too much cocaine (an overdose) is not uncommon. Cocaine can cause large increases in blood pressure that may result in bleeding within the brain. Constriction of brain blood vessels can also cause a stroke. An overdose of cocaine can cause breathing and heart problems that could result in death. This is what killed the University of Maryland basketball player, Len Bias, in 1986. Comedian John Belushi also died from a cocaine/heroin overdose in 1982.

Cocaine is highly "reinforcing": when it is given to animals, they will give it to themselves. In fact, if animals are given the choice, they will put up with electrical shocks and give up food and water if they can get cocaine.

Cocaine acts by blocking the reuptake of the neurotransmitters dopamine, norepinephrine and serotonin in the brain. Therefore, these neurotransmitters stay in the synaptic cleft for a longer time. Research has also shown that cocaine can also cause the release of dopamine from neurons in the brain.

Cocaine can also affect the peripheral nervous system. These effects include constriction of blood vessels, dilation of the pupil and irregular heart beat.

The Brain on Cocaine

PET image

These two images of the brain are positron emission tomography (PET) scans of a normal person (picture on the left) and of a person on cocaine (picture on the right). The PET scan shows brain function by seeing how the brain uses glucose, the energy source for neurons. In these scans, the red color shows high use of glucose, yellow shows medium use and blue shows the least use of glucose. Notice that many areas of the brain of the cocaine user do not use glucose as effectively as the brain of the normal person. This can be observed by the lower amounts of red in the right PET scan.

Image courtesy of the National Institute on Drug Abuse; used with permission.

Did you know?

The word "coca" comes from the Aymara language "khoka," meaning "the tree." Aymara is a disappearing language spoken by people who live in the Andes mountains of Bolivia and Peru.

Take a short on-line, interactive quiz about amphetamines, cocaine and marijuana.

For more information on cocaine and cocaine abuse, see:
  1. Cocaine Abuse from the National Institute on Drug Abuse.
  2. Cocaine - from the ADA
  3. Cocaine - from the National Families in Action

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