Uppers are stimulants that initially increase energy and alertness.
These are the world’s most widely used psychoactive drugs. Some give
an intense rush while others are only mildly stimulating. These drugs
vary from cocaine and amphetamines (strong stimulants) to caffeine and
nicotine (weaker ones). Stimulants also include drugs used to treat
attention-deficit/hyperactivity disorder, diet pills, and plant stimulants
such as khat, betel nut, ephedra, and yohimbe. New illicit stimulants
include MDPV, mephedrone and other cathinones sold deceptively as
“bath salts”. All stimulants can cause severe health problems when they
are abused. It is the rapid development of tolerance and the disrupting
effect on brain chemistry that encourage abuse and addiction. This
chapter surveys the various stimulants, their history, effects and side
effects, and the social context of their use.
Cocaine and amphetamines are the strongest stimulants, they
release excess neurotransmitters, principally epinephrine,
norepinephrine, and dopamine (the catecholamine neurotransmitters). At
lower doses, stimulation, confidence, aggressiveness, lack of hunger or
thirst, faster heart rates, raised blood pressure, and alertness are the
desired effects. At high doses or with prolonged use, neurotransmitter
depletion, exhaustion, paranoia, psychosis, dehydration, unhealthy
weight loss, and uncontrolled heart rates are common. The method of
use can increase the abuse potential; smoking cocaine in its freebase
chemical form known as “crack” is more addicting than snorting the drug.
Amphetamine congeners are used mainly to treat attention-
deficit/hyperactivity disorder and Amphetamine congeners are drugs that
are related to amphetamines but are not as strong. The most well known
is methylphenidate, used to treat attention-deficit/hyperactivity disorders.
There is much controversy over their use. Amphetamines such as
Adderall are also used to treat ADHD. The other well-known
amphetamine congeners are also used as diet pills such as
dexfenfluramine, pemoline, and phentermine. Use of a combination of
congeners known as fen-phen has diminished due to damaging side
effects such as heart problems.
Worldwide, plant stimulants such as betel nuts and khat are used
recreationally as often as coffee or cigarettes are used in the United
States. Khat is popular in eastern Africa, the Middle East, and southern
Arabia. Betel nuts have been used for more than two millennia;