Clinical Psychology
Drug treatments for schizophrenia
Name of drug
Chlorpromazine
Typical or atypical?
Typical
How does it work
Side effects/risk of relapse?
Research studies
Blocks dopamine receptor
sites and thus decreases
dopamine activity
Muscle tightening in neck and jaw, tardive dyskinesia,
decrease of spontaneous movement, , decrease in
emotional spontaneity and motivation, motor
restlessness and fidgeting, sedation, dry mouth,
constipation, weight gain, neuroleptic malignant
syndrome (can be fatal)
Barlow & Durand (1995) chlorpromazine
is effective in reducing schizophrenic
symptoms in about 60% of cases. Most
impact on positive symptoms; treated
patients may still suffer from severe
negative symptoms.
Haloperidol
Typical
Blocks dopamine receptor
sites and thus decreases
dopamine activity
55% relapse rate in Schooler et al (2005) study. Side
effects same as above.
Clozapine
Atypical
Blocks both dopamine and
serotonin receptor sites.
Similar side effects to typical anti-psychotics but tardive
dyskinesia much reduced. Fewer side effects than
typical or first generation anti-psychotics. Rare side
effect: agranulocytosis, (dangerously low levels of white
blood cells) can be fatal.
Risperidone
Atypical
Blocks both dopamine and
serotonin receptor sites.
Lower relapse rate than haloperidol, 45% compared
with 55%, (Schooler et al 2005); Also fewer side effects
than haloperidol; similar side effects to typical antipsychotics; weight gain, severe anxiety, sedation,
insomnia, sexual dysfunction, low blood pressure,
muscle stiffness, muscle pain, tremors, increased
salivation, and stuffy nose. Also associated with
diabetes, increased risk of suicide and tumors.
Schooler et al (2005) randomly allocated
555 patients in first episode of
schizophrenia, to either treatment with
haloperidol or risperidone. In both groups
75% showed a reduction in symptoms.
Pickar et al (1992) compared clozapine
with other neuroleptics and a placebo and
found clozapine to be the most effective
in reducing symptoms, even in patients
who had previously been treatment
resistant.
Emsley (2008) found that patients who
were injected with risperidone early in
course of disorder had low relapse rates
and high remission rates; 84% of patients
showed at least a 50% reduction in both
+ve and –ve symptoms and 64% went into
remission.