Hallucinogens

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Psychoactive Drugs
psychological, there is no doubt that tobacco smoking can be a difficult habit to break
(Breteler et al., 2004; Shiffman et al., 1997). It is also clearly recognized as a major risk
factor for cancer, heart disease, and respiratory disorders (U.S. Department of Health
and Human Services, 2001c).
MDMA The stimulant “Ecstasy,” or MDMA (short for 3,4-methylenedioxymethamphetamine), is a popular drug on college campuses in the United States (Strote, Lee, &
Wechsler, 2002). MDMA increases the activity of dopamine-releasing neurons, so it
leads to some of the same effects as those produced by cocaine and amphetamines
(Steele, McCann, & Ricaurte, 1994). These include a sense of well-being, increased sex
drive, and a feeling of greater closeness to others. Unfortunately, MDMA may also cause
dry mouth, hyperactivity, jaw muscle spasms that may result in “lockjaw,” elevated
blood pressure, fever, dangerously abnormal heart rhythms, and visual hallucinations
(Smith, Larive, & Romananelli, 2002). The hallucinations may appear because MDMA
is a serotonin agonist and also increases serotonin release (Green, Cross, & Goodwin,
1995). On the day after using MDMA—also known as “XTC,” “clarity,” “essence,” “E,”
and “Adam”—people often report muscle aches, fatigue, depression, and poor concentration (Peroutka, Newman, & Harris, 1988).
Even though it does not appear to be physically addictive, MDMA is a dangerous,
potentially deadly drug, especially when taken by women (Liechti, Gamma, & Vollenweider, 2001; National Institute on Drug Abuse, 2000). It permanently damages the
brain, killing serotonin-sensitive neurons (Green et al., 1995), as well as neurons that
use dopamine. As you might expect, the danger of brain damage increases with higher
doses and continued use (Battaglia, Yeh, & DeSouza, 1988). MDMA also impairs memory (Reneman et al., 2001; Rodgers, 2000; Zakzanis & Young, 2001), and users may
develop the symptoms of panic disorder, which include intense anxiety and a sense of
impending death (see the chapter on psychological disorders).
Opiates
The opiates (opium, morphine, heroin, and codeine) are unique in their capacity for
inducing sleep and relieving pain (Julien, 2005). Opium, derived from the poppy plant,
relieves pain and causes feelings of well-being and dreamy relaxation (Cowan et al.,
2001). One of its most active ingredients, morphine, was first isolated in the early 1800s.
It is used worldwide for pain relief. Percodan and Demerol are some common morphinelike drugs. Heroin is derived from morphine but is three times more powerful, causing
intensely pleasurable reactions. Opiates have complex effects on consciousness. Drowsy,
cloudy feelings occur because opiates depress activity in some areas of the cerebral cortex. They also create excitation in other parts, causing some users to experience euphoria, or elation (Bozarth & Wise, 1984). Opiates exert many of their effects by stimulating the receptors normally stimulated by endorphins, the body’s own painkillers. This
action “tricks” the brain into an exaggerated activation of its painkilling and moodaltering systems (Julien, 2005).
Opiates are highly addictive, partly because they stimulate a type of glutamate receptor in the brain’s neurons that causes physical changes in these neurons. It may be, then,
that opiates alter neurons so that they come to require the drug to function properly.
Beyond the hazard of addiction itself, heroin addicts risk death through overdoses, contaminated drugs, or AIDS contracted through sharing needles (Hser et al., 2001).
opiates Psychoactive drugs that produce both sleep-inducing and painrelieving effects.
hallucinogens Psychoactive drugs that
alter consciousness by producing a temporary loss of contact with reality and
changes in emotion, perception, and
thought.
Hallucinogens
Hallucinogens, also called psychedelics, create a loss of contact with reality and alter
other aspects of emotion, perception, and thought. They can cause distortions in body
image (the user may feel gigantic or tiny), loss of identity (confusion about who one
actually is), dream-like fantasies, and hallucinations. Because these effects resemble
many severe forms of mental disorder, hallucinogens are also called psychotomimetics
(“mimicking psychosis”).
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Chapter 4 Consciousness
LSD One of the most powerful hallucinogens is lysergic acid diethylamide, or LSD. It
was first synthesized from a rye fungus by a Swiss chemist, Albert Hofmann. In 1938,
after Hofmann accidentally ingested a tiny amount of the substance, he discovered the
drug’s strange effects in the world’s first LSD “trip” (Julien, 2005). LSD hallucinations
can be quite bizarre. Time may seem distorted, sounds may cause visual sensations, and
users may feel as if they have left their bodies. These experiences probably result from
LSD’s action as a serotonin agonist, because serotonin antagonists greatly reduce LSD’s
hallucinatory effects (Leonard, 1992).
The effects of LSD on a particular person are unpredictable. Unpleasant hallucinations and delusions can occur during a person’s first—or two hundredth—LSD experience. Although LSD is not addictive, tolerance to its effects does develop. Some users
suffer lasting side effects, including severe short-term memory loss, paranoia, violent
outbursts, nightmares, and panic attacks (Gold, 1994). Sometimes “flashbacks” can
occur, in which a person suddenly returns to an LSD-like state of consciousness weeks
or even years after using the drug.
Oxycodone, a morphine-like drug prescribed
by doctors under the label OxyContin,
has become popular among recreational
substance abusers. It was designed as a
timed-release painkiller, but when people
crush OxyContin tablets and then inject
or inhale the drug, they get a much
stronger and potentially lethal dose, especially when they are also using other
drugs such as alcohol or cocaine (Cone
et al., 2004). Deaths from OxyContin
abuse are already on the rise in the
United States (U.S. Drug Enforcement
Administration, 2002).
ANOTHER DRUG DANGER
Ketamine Ketamine is an anesthetic used by veterinarians to ease pain in animals,
but because it also has hallucinogenic effects, it is being stolen and sold as a recreational
drug known as “Special K.” Its effects include dissociative feelings that create what some
users describe as an “out-of-body” or “near-death” experience. Ketamine can also lead
to lasting memory problems (Curran & Monaghan, 2001; Smith et al., 2002), possibly
because it damages memory-related brain structures such as the hippocampus (JevtovicTodorovic et al., 2001).
Marijuana A mixture of crushed leaves, flowers, and stems from the hemp plant
(Cannabis sativa) makes up marijuana. The active ingredient is tetrahydrocannabinol,
or THC. When inhaled, THC is absorbed in minutes by many organs, including the
brain, and it continues to affect consciousness for a few hours (O’Leary et al., 2002).
THC tends to collect in fatty deposits of the brain and reproductive organs, where it
can remain for weeks. Low doses of marijuana may initially create restlessness and hilarity, followed by a dreamy, carefree relaxation, an expanded sense of space and time,
more vivid sensations, food cravings, and subtle changes in thinking (Kelly et al., 1990).
There is an ongoing debate about the dangers and potential benefits of marijuana
(Henquet et al., 2005; Iversen & Snyder, 2000; Strang, Witten, & Hall, 2000). Its dangers are suggested by the fact that a mild withdrawal syndrome has been reported in
rats; in humans, withdrawal from marijuana may be accompanied by increases in anxiety, depression, irritability, restlessness, and aggressiveness (Budney et al., 2001, 2003;
Haney et al., 1999; Kouri, Pope, & Lukas, 1999; Rodriguez de Fonseca et al., 1997; Smith,
2002). Further, marijuana interacts with the same dopamine and opiate receptors that
heroin acts on (Tanda, Pontieri, & Di Chiara, 1997), leading some researchers to speculate that marijuana might be a “gateway” to the use of opiates (Lynskey et al., 2003).
Other researchers have cautioned that the interpretation of these results is not clearcut (Grinspoon, 1999), because sex and chocolate have their rewarding effects by activating those same neurotransmitter receptors—and few people would want to outlaw
those pleasures!
Regardless of whether marijuana is addicting or leads to the use of opiates, it can
create a number of problems. It disrupts memory formation, making it difficult to carry
out mental or physical tasks; and, despite users’ impressions, it actually reduces creativity (Bourassa & Vaugeois, 2001; Pope & Yurgelun-Todd, 1996). And because marijuana disrupts muscle coordination, driving while under its influence can be dangerous. In fact, motor impairment continues well after the subjective effects of the drug
have worn off. Marijuana easily reaches a developing fetus and therefore should not be
used by pregnant women (Fried, Watkinson, & Gray, 1992). Finally, long-term use can
lead to psychological dependence (Stephens, Roffman, & Simpson, 1994), as well as to
impairments in reasoning and memory that last for months or years after marijuana
use stops (Bolla et al., 2002; Solowij et al., 2002). Research has also shown that adults
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in review
Psychoactive Drugs
MAJOR CLASSES OF PSYCHOACTIVE DRUGS
Main Effects
Potential for Physical/
Psychological Dependence
Relaxation, anxiety
reduction, sleep
Relaxation, euphoria
High/high
High/high
High/high
Alertness, euphoria
Moderate/high
“smokes,”“coffin nails”
“Ecstasy,” “clarity”
Alertness
Alertness
Hallucinations
Moderate to high/high
Moderate/moderate
High (?)/high
Low/(?)
Opiates
Opium
Morphine
Heroin
Percodan, Demerol
“junk,”“smack”
Euphoria
Euphoria, pain control
Euphoria, pain control
High/high
High/high
High/high
Hallucinogens
LSD/ketamine
“acid”/“Special K”
Low/low
Marijuana (cannabis)
“pot,”“dope,”“reefer”
Altered perceptions,
hallucinations
Euphoria, relaxation
Drug
Trade/Street Name
Depressants
Alcohol
Barbiturates
GHB
“booze”
Seconal, Tuinal, Nembutal (“downers”)
G, Jib, Scoop, GH Buddy
Stimulants
Amphetamines
Cocaine
Caffeine
Nicotine
MDMA
?
Benzedrine, Dexedrine, Methadrine
(“speed,” “uppers,” “ice”)
“coke,”“crack”
冧
冧
Low/moderate
1. Physical dependence on a drug is a condition more commonly known as
.
2. Drugs that act as antagonists
the interaction of neurotransmitters and receptors.
3. Drug effects are determined partly by what we learn to
the effects to be.
who frequently used marijuana scored lower than nonusers with equal IQs on a twelfthgrade academic achievement test (Block & Ghoneim, 1993) and that heavier use in
teenagers is associated with the later appearance of anxiety, depression, and other symptoms of mental disorder (Arsenault et al., 2004; Patton et al., 2002; Zammit et al., 2002).
Marijuana may have considerable value in some domains, however. Doctors have successfully used it in the treatment of asthma, glaucoma, epilepsy, chronic pain, and nausea from cancer chemotherapy; it may even help in treating some types of cancer (Gorter
et al., 2005; Parolaro et al., 2002; Rog et al., 2005; Tramer et al., 2001). But critics say
medical legalization of marijuana is premature until more controlled research is available to establish its medicinal value. They point out, too, that even though patients tend
to prefer marijuana-based drugs, other medications may be equally effective and less
dangerous (e.g., Campbell et al., 2001; Fox et al., 2004; Hall & Degenhardt, 2003).
Nevertheless, in Canada, it is legal to grow and use marijuana for medicinal purposes, and the same is true in eight U.S. states, despite federal laws to the contrary and
the threat of federal intervention to enforce those laws (Okie, 2005). The American
Medical Association has rejected the idea of medical uses for marijuana, but scientists
are intent on objectively studying its potential value in the treatment of certain diseases, as well as its possible dangers. Their work is being encouraged by the National
Institute of Medicine (Joy, Watson, & Benson, 1999), and drug companies are working
on new cannabis-based medicines (Altman, 2000; Tuller, 2004). The United Nations,
too, has recommended that governments worldwide sponsor additional work on the
medical uses of marijuana (Wren, 1999). (“In Review: Major Classes of Psychoactive
Drugs” summarizes our discussion of these substances.)