Drug Types 15same effects that lower doses once provided. That suggests an abuser has
developed “tolerance” to the drug, a classic component of addiction. In con-
trast to abusers of other drugs, amphetamine abusers commonly fight toler-
ance not by gradually increasing their dose but by alternating between periods
of little use and binges of massive use, a practice promoting inconsistent be-
havior that can bewilder acquaintances. Despite all of this, into the 1980s am-
phetamines were described as not addictive.
Although amphetamines have a long history and widespread usage, their
potential for causing cancer is unknown; necessary animal experiments had
not been conducted as the twentieth century closed. Abnormal fetal devel-
opment has occurred in mice receiving over 40 times the maximum safe hu-
man dose, but normal development of offspring has occurred despite
administration of 12.5 times the maximum human dose to rats and 7 times
the maximum to rabbits.^5 One human study noted a tendency for more cleft
palates than usual if mothers used amphetamines during the first two months
of pregnancy.^6 Amphetamines easily pass from a pregnant woman into the
fetal blood supply. Standard medical advice cautions pregnant women against
using the drug without first discussing the issue with a physician. Some stud-
ies claim to find that children born of women who abused amphetamines
during pregnancy will have long-term problems with personality and intelli-
gence—but these same women abused other drugs as well; some were dis-
pleased about their pregnancies; and about 80% of children in one study had
been taken away from the mothers and put into foster homes.^7 Problems faced
by such youngsters may well originate outside amphetamines. Tracking am-
phetamines’ physical effect on offspring is easier. Babies from women who
abused amphetamines during pregnancy can exhibit anxiety and physical dis-
comfort suggesting dependence and withdrawal. We know that excessive use
by a pregnant woman can promote premature birth and reduce a newborn’s
weight. Genetic predisposition appears to influence how much this type of
drug will affect fetal development.
Amphetamines enter human milk and can reach levels three to seven times
higher than shown in maternal blood, so nursing mothers can be dosing their
infants. Because this kind of drug can act as an appetite suppressant, causing
a person to take in inadequate nutrition, that effect is still another concern if
infants receive amphetamines through a mother’s milk.
For information about specific amphetamine class stimulants, see alphabet-
ical listings for:dextroamphetamine,ephedrine,khat,ma huang,metham-
phetamine,methcathinone, andmethylphenidate.
Anorectic Class
Many persons in the United States consider themselves overweight. That
self-perception may be more prevalent than obesity itself, but even so, by
medical standards a good 33% to 50% of Americans are overweight.^8 That
condition can aggravate or even cause serious physical afflictions such as di-
abetes, high blood pressure, and heart disease. Persons seeking slimness and
who are dissatisfied with results from changes in diet and exercise may seek
pharmacological help.