Exploring Different Kinds of Drugs
Most of the drugs that people abuse have their effect on the limbic
system of the brain. The limbic system is located deep within the
brain near the top of the brain stem. The limbic system produces the
feelings of pleasure, pain, anger, and fear which characterize our
emotions. All drugs of addiction work on our emotions. If a certain
drug makes us feel very good, we tend to want to take that drug again
and again. It is because of this temporary good feeling that we become
psychologically addicted to a drug.
Within the limbic system, drugs work on the brain by way of
neurotransmitters. Neurotransmitters are the chemicals which allow our
nerve cells to communicate with each other. Some of the
neurotransmitters affected by drugs are serotonin, norepinephrine and
dopamine. The class of drugs called stimulant drugs will usually make
more a neurotransmitter(s) available to the brain. The class known as
depressant drugs will usually make less of a neurotransmitter(s)
available to the brain. Because our brain adjusts to this alteration
in neurotransmitters, our brain may become physiologically
(physically) dependent on some drugs. Although our brain can become
physiologically dependent on a wide variety of drugs, the brain is
more likely to become dependent on depressant drugs than on stimulant
As drugs appear in nature they can be addictive. However, it is
technology which makes them very addictive. Opium, a drug which occurs
naturally in the white poppy plant, is classed as a narcotic. A
narcotic drug relieves pain and induces sleep. The brain has
neurotransmitters which controls our perception of pain. These
neurotransmitters are called endorphins. Within the brain, endorphins
mask pain and make us feel good. All opium products are chemically
similar to endorphins and have their pleasurable effects by
substituting for endorphins in our brain.
Opium has been used and abused since the beginning of recorded
history. There is a reference to opium in Homer's Odyssey written in
the sixth century BCE. People have for centuries eaten and smoked
opium. Some of these people became addicted to it, others did not.
However, in the mid 1800's, opium was refined into morphine and
codeine. Morphine and codeine magnified the power of opium ten times.
Also in the mid 1800's, the hypodermic needle was invented. If the
hypodermic needle is used to intravenously inject morphine, it
magnifies the power of the drug 10-15 times.
In 1896 opium was further refined into diacetylmorphine, which became
known as heroin. It was named heroin because they thought it was a
"hero" drug. It was believed to be nonaddictive, and for years was a
treatment for alcoholism. Alcoholics were advised to stop drinking and
substitute heroin use instead. This was...