(2) Physical dependence. In physical dependence, a drug becomes
necessary in order for a person to function physically. This exists only if withdrawal
symptoms occur when the drug use stops or if tolerance to the drug has developed.
1-3.
CATEGORIES OF COMMONLY ABUSED SUBSTANCES
Drug abuse is not limited to one particular group of individuals. The majority of
Americans is vastly overmedicated in one way or another, which is most likely due to
the belief that there is a pharmacologic remedy for every problem. The list of commonly
abused substances can be extremely long, ranging from caffeine and tobacco (nicotine)
to over-the-counter sleep medications. We will limit this lesson to abused substances
that fall into four major categories: depressants, stimulants, narcotics, and
a. Depressants (Downers). Depressants are substances that affect the central
nervous system (CNS). They decrease awareness and the mental capacity to function,
slow reflexes, and may decrease the respiratory and heart rates.
(1) Alcohol. Alcohol is a liquid obtained by fermentation of carbohydrates
with yeast. It is a powerful CNS depressant.
(2) Barbiturates (sedatives/hypnotics). Barbiturates are drugs that affect the
CNS with remarkable effects similar to that of alcohol. They do not relieve pain, nor do
they produce a specific "high." Sometimes an individual will use barbiturates with
alcohol or with the opium analgesics to augment the effects of a weaker product.
(3) Nonbarbiturates (sedatives/hypnotics). Nonbarbiturates are drugs
known as tranquilizers (drugs used to reduce mental disturbance, such as anxiety and
tension). Some of the drugs are Thorazine, Valium, and Librium.
b. Stimulants (Uppers). Stimulants are drugs that affect the nervous system by
increasing alertness, awareness, and mental and motor activity. In other words, they
are known to excite the user. The effect on the individual will depend on the route of
administration, the drug, its dose, and the circumstances. Some of the drugs in this
category are listed below.
(1) Amphetamines. Amphetamines are stimulants taken to produce a
general mood elevation. They include Dexedrine, Benzedrine, and Methedrine.
(2) Cocaine (street name is coke). Cocaine is a powerful stimulant that
induces an extreme state of euphoria. It is often inhaled.
(3)
Caffeine. Caffeine is a mild stimulant found in coffee, cola drinks, tea,
and cocoa.
Nicotine. Nicotine is a mild stimulant found in tobacco.
(4)
MD0549
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