Technically, any substance other than food
that alters our bodily or mental functioning is a drug.
Many people mistakenly believe the term
"drug" refers only to some sort of medicine or
a illegal chemical taken by drug addicts.
They don't realize that familiar substances
such as alcohol and tobacco are also drugs.
This is why the neutral term "substance"
is now used by many physicians and psychologists.
The phrase "substance abuse" is
often used instead of "drug abuse" to make clear
that substances such as alcohol and tobacco can be just
as harmfully misused as heroin or cocaine.
We live in a society in which the medicinal
and social use of substances is pervasive: an aspirin to
quiet a headache, some wine to be sociable, coffee to get
going in the morning, a cigarette for the nerves.
When do these socially acceptable and apparently
constructive uses of a substance become mis- uses?
First of all, most substances take in excess
will produce negative effects, such as poisoning or intense
Repeated use of a substance can also lead
to physical addiction or substance dependence.
Dependence is marked, first by an increased
tolerance, with more and more of the substance required
to produce the desired effect, ad then by the appearance
of unpleasant withdrawal symptoms when the substance is