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Psychoactive Drugs

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Psychoactive Drugs
525
Biological Treatments
ELECTROCONVULSIVE THERAPY
Estimates of the number of people receiving ECT each year in the United States
range from 30,000 to over 100,000
(Hermann et al., 1995; Mathew, Amiel, &
Sackeim, 2005). A survey in the United
Kingdom suggests that about 12,000 patients a year are receiving ECT (U.K. Statistical Bulletin, 1999). Because of its
dramatic and potentially dangerous nature, the use of ECT remains controversial
(Breggin, 1997). Critics want it outlawed,
but proponents say the benefits of ECT
for certain patients outweigh its potential costs.
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Effects.
electroconvulsive therapy (ECT) A
brief electric shock administered to the
brain, usually to reduce severe depression that does not respond to drug
treatments.
neuroleptics Drugs that relieve the
symptoms of schizophrenia or other severe forms of psychological disorder.
Also called antipsychotics.
because schizophrenia and epilepsy rarely occur in the same person, epileptic-like
seizures might combat schizophrenia. In 1938, Italian physicians Ugo Cerletti and Lucio
Bini created seizures by passing an electric current through the brains of people with
schizophrenia. During the next twenty years or so, this procedure, called electroconvulsive therapy (ECT), became a routine treatment for schizophrenia, depression, and
sometimes mania. Although many patients improved, they often relapsed. The benefits
of ECT also had to be weighed against side effects such as memory loss, confusion,
speech disorders, and, in some cases, death due to cardiac arrest (Lickey & Gordon,
1991; Shiwach, Reid, & Carmody, 2001).
To make ECT safer, patients are now given an anesthetic so that they are unconscious before the shock is delivered, along with a muscle relaxant to prevent bone fractures during convulsions. Also, the shock now lasts only about half a second and is usually delivered to only one side of the brain (Sackeim et al., 2000). Finally, in contrast
to the dozens of treatments administered decades ago, patients now receive only about
six to twelve shocks, one approximately every two days (Fink, 1999).
Although we still don’t know for sure how and why ECT works (Greenberg &
Kellner, 2005; Rudorfer, Henry, & Sackheim, 1997; Sackeim, 1994), it is being performed
more frequently in the United States than coronary bypass operations, appendectomies,
and tonsillectomies (Mathew, Amiel, & Sackeim, 2005). It is administered mainly to
patients suffering severe depression (and occasionally to manic patients) who do not
respond to less drastic treatments (Daly et al., 2001; de Macedo-Soares et al., 2005;
Rasmussen, 2003). ECT can be effective in such cases—especially when followed up
with medication—and it does not appear to cause brain damage, even when administered repeatedly (e.g., Anghelescu et al., 2001; Dwork et al., 2004; Kellner et al., 2005;
Sackeim et al., 2001). Nevertheless, researchers are looking for even safer methods of
inducing seizures. Among the techniques being investigated are magnetic seizure therapy (MST), which creates seizures with timed pulses of magnetic energy (Lisanby,
2004), and a related but less intense procedure called repetitive transcranial magnetic
stimulation (rTMS; Avery et al., 2006; Couturier, 2005; Schutter, 2005).
Psychoactive Drugs
The use of ECT declined after the 1950s, in part because psychoactive drugs had begun
to emerge as more convenient and effective treatment alternatives. In the chapters on
biology and behavior and on consciousness, we discuss the effects of psychoactive drugs
on neurotransmitter systems, autonomic activity, emotions, thinking, and behavior. Here,
we describe their role in combating schizophrenia, depression, mania, and anxiety.
Neuroleptics One group of drugs, called neuroleptics or antipsychotics, dramatically reduces the intensity of psychotic symptoms such as hallucinations, delusions,
paranoid suspiciousness, disordered thinking, and confused speech in many mental
patients, especially those with schizophrenia. The most widely used antipsychotic drugs
are the phenothiazines (pronounced “fee-noh-THIGH-uh-zeens”), of which the first,
chlorpromazine (marketed as Thorazine in the United States and as Largactil in Canada
and the United Kingdom), has been especially popular. Another neuroleptic, haloperidol (Haldol), is about as effective as the phenothiazines, but it creates less sedation
(Julien, 2005). Patients who do not respond to one type of neuroleptic may respond to
the other (Davis, Chen, & Glick, 2003). Between 60 and 70 percent of patients receiving these drugs show improvement, though fewer than 30 percent respond well enough
to live successfully on their own.
Neuroleptics have side effects ranging from dry mouth and dizziness to symptoms
similar to those of Parkinson’s disease, including muscle rigidity, restlessness, tremors,
and slowed movement. Some of these side effects can be treated with medication, but
at least 25 percent of patients who take chlorpromazine or haloperidol for several years
develop an irreversible movement disorder. This disorder, called tardive dyskinesia (TD),
causes uncontrollable, repetitive actions, often including twitching of the face, flailing
of the arms and legs, and thrusting of the tongue.
526
Chapter 13 Treatment of Psychological Disorders
An herbal remedy
from a plant called Saint John’s wort has
become a popular nonprescription treatment for depression. One of its active ingredients, hypericin, is thought to affect
neurotransmitters in the brain much as
Prozac does. Double-blind, placebocontrolled studies have shown Saint John’s
wort to be as effective as Prozac for
depression (e.g., Hammerness, Basch, &
Ulbricht, 2003; Hypericum Depression Trial
Study Group, 2002; Szegedi et al., 2005).
The design of some of these studies has
been questioned, however (e.g., Spira,
2001), so final conclusions about the
safety and effectiveness of Saint John’s
wort must await the results of further
research.
A NATURAL CURE?
antidepressants
depression.
Drugs that reduce
Among a newer generation of antipsychotic drugs (also called atypical neuroleptics) is
clozapine (Clozaril), which has effects like those of the phenothiazines but is less likely to
cause movement disorders except at high doses (Louzá & Bassitt, 2005; Rochon et al.,
2005). Although no more effective overall than the phenothiazines, clozapine has helped
many patients who did not respond to the phenothiazines or haloperidol (Green & Patel,
1996; Rabinowitz et al., 2001). Unfortunately, taking clozapine carries a slight risk of developing a fatal blood disease called agranulocytosis (Alvir et al., 1993). Weekly blood tests to
detect early signs of this disease greatly increase the cost of using this drug (Meltzer, 1997).
Several other atypical neuroleptics have been introduced recently, including risperidone (Risperdal), olanzapine (Zyprexa), quetiapine (Seroquel), ziprasidone (Geodon),
and, most recently, aripiprazole (Abilify). These medications are expensive, but they
have fewer side effects than clozapine, and they do not cause agranulocytosis (Correll,
Leucht, & Kane, 2004). Like clozapine, they also appear to reduce the “negative” symptoms of schizophrenia, such as lack of emotion, social withdrawal, and reduced speech
(e.g., Kane et al., 2003; Kapur, Sridhar & Remington, 2004; Lieberman et al., 2003;
Potkin et al., 2003). There is some doubt, though, whether these newest atypical neuroleptics are significantly more effective than older drugs, partly because 60 to 80 percent of patients may stop taking them because of weight gain, nervous tics, and other
bothersome side effects (Lieberman et al., 2005; Miyamoto et al., 2005).
Antidepressants Soon after antipsychotic drugs appeared, they were joined by
antidepressants, a class of drugs that is now widely prescribed for relieving the symp-
toms of depression (National Institute for Clinical Excellence, 2004; Olfson et al., 2002).
There are several classes of antidepressant drugs. The monoamine oxidase inhibitors
(MAOIs) are used to treat many cases of depression, especially with clients who also
experience anxiety and panic (Julien, 2005). The tricyclic antidepressants (TCAs) are
another popular class of antidepressants. The TCAs have been prescribed more frequently than MAOI drugs because they seem to work somewhat better and have fewer
side effects. However, overdoses of TCAs can be fatal, as can taking TCAs and drinking alcohol at the same time (Nutt, 2005a).
The most prominent of several newer antidepressants is fluoxetine (Prozac). Introduced in 1986, fluoxetine quickly became the most widely used antidepressant in North
America. Its popularity is due to the fact that it is about as effective as older drugs and,
in most cases, has fewer and milder side effects—mainly weight gain, sexual dysfunction, and gastrointestinal problems (Cookson & Duffett, 1998; Nutt, 2005a; Patten
et al., 2005). An improved version of Prozac, R-fluoxetine, is currently being developed,
and other, even newer antidepressants also show promise. These include bupropion
(Wellbutrin), venlafaxine (Effexor), nefazodone (Serzone), escitalopram (Lexapro), and
duloxetine (Cymbalta; Appleton, 2000; Brambilla et al., 2005; Hirschfeld & Vornik,
2004, Zimmerman et al., 2005).
About 50 to 60 percent of patients who take antidepressant drugs show improved
mood, greater physical activity, increased appetite, and better sleep (Hollon, Thase, &
Markowitz, 2002). However, only about 10 to 20 percent of people suffering the most
severe psychotic depression show this same amount of improvement (U.S. Surgeon
General, 1999). It has long been assumed that the effects of antidepressant drugs were
due to the chemical action of their active ingredients, but there is some doubt about
this assumption. An analysis of clinical trial data submitted to the U.S. Food and Drug
Administration by the makers of six widely prescribed antidepressant drugs showed
that in 57 percent of the trials, antidepressant drugs did only a little better than placebo
medications (“sugar pills”) at relieving depression (Kirsch et al., 2002; Kirsch, Scoboria, &
Moore, 2002). Defenders of antidepressant medications argue that even relatively small
effects are better than none (e.g., Thase, 2002), whereas critics contend that those effects
are too small to matter (Moncrieff & Kirsch, 2005).
The mineral salt lithium carbonate, when taken
regularly, prevents both the depression and the mania associated with bipolar disorder
Lithium and Anticonvulsants
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