Modifying Schziophrenia - Antipsychotic Drugs

Question 1

Conventional antipsychotic

Answer 1

First generation of antipsychotic drugs (chlorpromazine - low potency, require large amount for effect)
(Haloperidol - 50 times more effective = less dosage needed = less side effects)

Most antagonist

Question 2

How conventional drugs work

Answer 2

Block D2 receptors in (block dopamine in):
-Mesolimbic system: reduce positive symptoms
-mesocortical system: cause emotional + cognitive problems
-nigrostriatal system: problem with motor control
Has great effect on decreasing high level of dopamine in mesolimbic system
dopamine
Due to areas with normal dopamine level having decrease level in
Can also cause weight gain, diabetes, hypertension

Question 3

Atypical antipsychotic

Answer 3

Second generations
Most are partial agonist and antagonist (Clozapine)
(Aripiprazole)
Partial agonist- effects not as strong as antagonist, but produce less severe side effects

Question 4

How atypical antipsychotics work

Answer 4

Block D2 receptors in (block dopamine):
-Mesolimbic system: reduce positive symptoms
-mesocortical system
-nigrostriatal system

Also block 5-HT2A receptors in (block serotonin in)
-mesocortical system
-nigrostriatal system
This causes dopamine level to increase in these areas
-so no problems in emotional + control problem
-no motor problems

Question 5

Seeman et al

Answer 5

Shows there is difference between 2 types
Atypical drug more loosely binded to receptors
-causes therapeutic effects, but not long enough for side effects as severe as conventional
Half life
-atypical shorter so falls off receptors within 24 hrs, conventional longer than 24 hrs

Question 6

Evaluation - effectiveness (strength)

Answer 6

Cole et al
-75% schizo given conventional antipsychotic considered ‘much improved’
-25% of those on placebo are
-0% of those on antipsychotic gotten their symptoms worse
Research shows the drugs are effective in the treatment
Lobos - clozapine + other atypical good at reducing positive symptoms

Question 7

Evaluation - effectiveness (weakness)

Answer 7

Lobos - Clozapine does not work well in patients who are resistant to

Poor adherence
Valentin et al - 63,000 schizo, 40% of cases had poor adherence rate (missed or refuse dosage)
-possibly due to side effects, they feel ‘normal’ again, or not aware they are sick

Only 5% showed poor adherence rate to clozapine
-due to drug has chance of agranulocytosis so need regular doctor check up

But some drugs may be more effective than other on particular people due to unknown reasons

Question 8

Evaluation - ethics (strength)

Answer 8

Strength:
-Does not require patient to be of right state of mind to work
-Schizo can suffer greatly, can cause self harm or harm other people.
-Can be argued it is more ethical to treat them than do nothing even against their consent

Question 9

Evaluation - ethics (weakness)

Answer 9

Side effects
-Parkinsonism - tremors + instability
-weight gain- lead to hypertension or diabetes
Steingard: those who take antipsychotic has brain shrinkage than
those doesn’t = less likely to work + maintain relationship

Do they really need it continuously?
Insel- 103 schizo those only take antipsychotic meds when they have symptoms more likely to get job + resume daily activity than those continuously on it - relapse rate same

Question 10

Evaluation - social implications

Answer 10

Adv:
Cost
-Antipsychotic drugs (clozapine) cheaper compare to therapy, or supporting hospital with nurse and equipments
-every can get them NHS provides it since cheap Schizo in work force

Disadv:
Tihonen et al - 37 fold increase in suicide in schizo not in hospital + not taking meds
NCISH - 6% of homicide in England cause by schizo 2003-2013
Side effects can cause further expensive treatment (overweight + high blood pressure)