c. The antipsychotic tranquilizers are neither habituating nor do they cause
physical dependence. However, the sedative effects for a given dose decrease with
prolonged use. That is, tolerance to the sedative effects (but not to the antipsychotic
effects) develops rapidly. All in all, the experience of taking an antipsychotic tranquilizer
is usually unpleasant to the client, since it makes him feel listless and easily fatigued.
3-14. TOXICITY CAUSED BY LARGE DOSES
In addition to the unpleasant side effects already discussed, there are other side
effects that may result from the large doses of phenothiazine-type drugs ordinarily
used. These include parkinsonism in which the muscles become rigid and there may
be fine tremors. The degree of muscle rigidity may vary from impairment of facial
expression to complete immobility of the body. Other effects may include dystonia (in
which muscle tonicity is disordered) and akathisia (a feeling of restlessness). These
effects -- parkinsonism, dystonia, and akathisia--are collectively called extrapyramidal
effects. Other possible adverse effects of these drugs are dizziness, slate-colored
pigmentation of the body and impaired vision (rarely). Allergic reactions to particular
drugs may occur; for example, jaundice may result from the use of chlorpromazine.
3-15. THERAPEUTIC USES
The phenothiazine-type drugs are useful in controlling excited activity and hostile
behavior in psychotic clients. In addition to sedation, these drugs produce other
beneficial changes in the behavior of psychotics, including non-excited schizophrenics.
Clinical records seem to indicate that schizophrenic clients tend to have a shorter stay
in mental hospitals when they are given phenothiazine-type tranquilizers. These drugs
are also useful in treating severe depression.
3-16. CHLORPROMAZINE HYDROCHLORIDE
a. Action and Uses. Chlorpromazine hydrochloride (Thorazine) acts to
depress the central nervous system and to relieve the symptoms of nausea and
vomiting. It is used to relieve anxiety, tension, and hyperactivity in psychotic and
psychoneurotic clients. It is used to treat nausea and vomiting associated with recovery
therapy, acute infections, cancer, and uremia. Also, it is used to relieve hiccups.
b. Administration. The drug may be given orally, intramuscularly, or
intravenously. The usual oral dose is 25 to 100 mg. The usual parenteral dose for mild
nausea and vomiting is 25 mg daily, given intramuscularly. For the severely disturbed
manic client, dosage is much higher, up to 400 mg daily. Because this drug is irritating
to tissue, it should be injected slowly, deep into the muscle. It is not to be given
subcutaneously. The site should be massaged to help reduce local irritation.
MD0913
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