A list of drugs utilized in the treatment of epilepsy is provided in the Appendix.
Detailed tables show doses, recommendations, expectations, side effects, con-
traindications, and more; available on the book’s Web site (see URL in Appendix).
Antipsychotics
Psychosis is a disorder that is characterized by a number of symptoms. These
include difficulty processing information and reaching a conclusion; experienc-
ing delusions or hallucinations; being incoherent or in a catatonic state; or
demonstrating aggressive violent behavior.
Psychosis is divided into major categories, once of which is schizophrenia.
Schizophrenia is a chronic psychotic disorder where patients exhibit either
positive or negative symptoms. Positive symptoms are exaggeration of normal
function such as agitation, incoherent speech, hallucination, delusion, and
paranoia. Negative symptoms are characterized by a decrease or loss of motiva-
tion or function such as social withdrawal, poor selfcare, and a decrease in the
content of speech. Negative symptoms are more chronic and persistent than
positive symptoms.
Psychosis is caused by an imbalance in the neurotransmitter dopamine in the
brain. Antipsychotic medication, also known as dopamine antagonists, block
the D 2 dopamine receptors in the brain thereby reducing the psychotic symptoms.
A number of antipsychotic medications block the chemoreceptor trigger zone
and vomiting (emetic) center of the brain. In doing so, it produces an antiemetic
effect. Although blocking dopamine improves the patient’s thought processes
and behavior, it can cause side effects.
These include symptoms of Parkinsonism (see Parkinsonism previously dis-
cussed in this chapter). Patients who undergo long-term treatment for psychosis
using antipsychotic medications also might be prescribed drugs to treat the
symptoms of Parkinsonism.
Antipsychotic medications are divided into two categories. These are some-
times called traditional and atypical. The typical category of antipsychotic med-
ication is further subdivided into phenothiazines and nonphenothiazines.
Phenothiazines block norepinephrine causing sedative and hypotensive effects
early in treatment.
Nonphenothiazines include butyrophenone haloperidol (Haldol) whose phar-
macologics are similar to phenothiazines as it alters the effects of dopamine by
blocking the dopamine receptor sites.
CHAPTER 15 Nervous System Drugs^295