Biological Therapy Flashcards
Typical Vs Atypical APs
TAP
= around since 1950s
E.g. chlorpromazine
AAP
= around since 1970s, aim of development was to maintain/improve effectiveness but minimise side effects
E.g. clozapine, risperidone
Administration & dosage of chlorpromazine
Tablets, syrup, injection
400-800mg
Orally = max. dose of 1000mg
How do TAPs work
Dopamine antagonists
- block DA receptors in brain synapses = reduce DA action
Initial taking of TAP = increase DA levels, but then decrease
= normalises neurotransmission in key brain areas
= reduce symptoms like hallucinations
Sedation effect of chlorpromazine
Believed to be due to effect on histamine receptors
- often used to calm individuals, not only SZPNics
- e.g. done when patients first admitted to hospitals & very anxious
How does Clozapine work
- same as TAPs, DA antagonist
+ act on serotonin and glutamate receptors
= believed this helps improve mood, & reduce depression/anxiety, may also improve cognitive functioning
When may clozapine be prescribed
Mood-enhancing effects = sometimes prescribed when individual considered high suicide risk
- 30-50% of SZPNics attempt suicide
Why was risperidone developed, how does it work
Attempt to produce drug as effective as clozapine but without serious side effect (agranulacytosis)
- same as clozapine, but bind more strongly to DA = effective in much smaller doses
Evidence to suggests leads to fewer side effects then other APs
Administration and Dosage of clozapine vs risperidone
Clozapine
not available as injection
daily dosage = 300-450 mg
Risperidone
all options
daily dosage = 4-8 mg, max 12 mg
Strength of APs for treating SZPN
Evidence for effectiveness
= large bodies of evidence supporting T/AAPS being atleast moderatively effective in tackling symptoms
- Thornley at al = data from 13 trails, over 1100 pps, comparing effects of chlorpromazine to control = chlorpromazine associated with better overall functioning and reduced symptom severity compared to placebo
= shows APs work
Weakness of APs for treating SZPN
Serious side effects
TAPs = associated with dizziness, agitation, sleepiness, stiff jaw, weight gain, itchy skin
most serious = neuroleptic malignant syndrome
- NMS results in high temp, delirium, coma, can be fatal
AAPs = potential fatal side effects of blood condition ‘agranulacytosis’ (severe lowered white blood cell count)
(clozapine)
= can do harm as well as good, avoidance of them if side effects experienced = makes treatment ineffective
Further weakness of APs for treating SZPN
Mechanism Unclear
= do not know how some of them work
- understanding strongly tied up with OG DA hypothesis, which is not complete as it does not include cortical hypodominergia
- if this is true, most APs should not work
= this along with already questioning effectiveness due to side effects = adds to argument of being ineffective
= atleast some APs may not be best opting treatment, other factors may be involved in apparent success
Why can biological therapy be seen as more appropriate than psychological therapy
Easy to administer
= simply remember to take required daily dosage
- less physical time and cognitive effort required
- symptoms such as speech poverty = unlikely to work well with CBT
+ no waiting list for therapist
= quicker symptom relief
link between APs and severe side effect of NMS
= believed to be caused by drug blocking DA action in hypothalamus (which regulates homeostasis/internal body temp.)
