Schizophrenia- Biological Therapies For SZ: Drug Therapy

Question 1

Antipsychotics -

Answer 1

Drugs used to reduce the intensity of symptoms, in particular the positive symptoms, of psychotic conditions like schizophrenia.

Question 2

Typical antipsychotics -

and example(s)

Answer 2

The first generation of antipsychotic drugs, having been used since the 1950s.
They work as dopamine antagonists and include Chlorpromazine.

Question 3

Atypical antipsychotics -

and example(s)

Answer 3

Drugs for schizophrenia (a psychotic disorder) developed after typical antipsychotics. They typically target a range of neurotransmitters such as dopamine and serotonin.

Examples include Clozapine and Risperidone.

Question 4

What is the most common treatment for schizophrenia?

Answer 4

The most common treatment for schizophrenia is antipsychotic drugs, which can be taken as tablets, syrup, or injections every 2-4 weeks for those at risk of not taking their medication regularly.

Question 5

How long do patients typically need to take antipsychotics for schizophrenia?

Answer 5

Some patients may require a short course of antipsychotics, while others may need them for life, depending on the recurrence of symptoms.

Question 6

What are the two main types of antipsychotics used in the treatment of schizophrenia?

Answer 6

The two main types are typical (traditional) antipsychotics and atypical (second-generation) antipsychotics.

Question 7

What is an example of a typical antipsychotic drug?

Answer 7

Chlorpromazine is an example of a typical antipsychotic.

Question 8

How is Chlorpromazine typically administered, and what is its dosage?

Answer 8

Chlorpromazine can be taken as tablets, syrup, or injections. The usual daily dosage is between 400-800mg, with a maximum of 1000mg, although the dosage is initially lower and gradually increased.

Question 9

How does Chlorpromazine work to reduce symptoms of schizophrenia?

Answer 9

Chlorpromazine works as a dopamine antagonist, blocking dopamine receptors in the brain to reduce dopamine activity, which helps normalize neurotransmission and reduce symptoms like hallucinations.

Question 10

What additional effect does Chlorpromazine have besides treating schizophrenia?

Answer 10

Chlorpromazine also acts as a sedative, likely due to its effect on histamine receptors, though the exact mechanism is not fully understood.

Question 11

When is Chlorpromazine typically used in addition to treating schizophrenia?

Answer 11

It is often used to calm patients with schizophrenia and other conditions, especially when patients are first admitted to the hospital and are anxious.

Question 12

What is an example of an atypical antipsychotic drug?

Answer 12

Clozapine is an example of an atypical antipsychotic.

Question 13

What is the history of Clozapine’s use?

Answer 13

Clozapine was developed in the 1960s, withdrawn in the 1970s due to fatal agranulocytosis, and then reintroduced in the 1980s after proving more effective than typical antipsychotics.

Question 14

What is the typical dosage for Clozapine, and how does it work?

Answer 14

The typical daily dosage for Clozapine is 300-450mg. It works by binding to dopamine, serotonin, and glutamate receptors, which may improve mood, reduce depression/anxiety, and enhance cognitive function.

Question 15

Why is Clozapine prescribed to patients at high risk of suicide?

Answer 15

Clozapine has mood-enhancing effects, which is important as 30-50% of people with schizophrenia attempt suicide at some point.

Question 16

What is another atypical antipsychotic drug used to treat schizophrenia?

Answer 16

Risperidone is another atypical antipsychotic used to treat schizophrenia.

Question 17

How is Risperidone administered, and what is its typical dosage?

Answer 17

Risperidone can be taken as tablets, syrup, or an injection lasting around two weeks. The typical daily dose is 4-8mg, with a maximum of 12mg.

Question 18

How does Risperidone differ from other antipsychotic drugs?

Answer 18

Risperidone binds more strongly to dopamine receptors than other antipsychotics like Clozapine, which allows it to be effective at smaller doses.

Question 19

What advantage does Risperidone have over other antipsychotics?

Answer 19

Risperidone is believed to result in fewer side effects compared to most other antipsychotics.

Question 20

Evaluation
Problems with the evidence for effectiveness

Answer 20

Although there is an impressive mass of evidence to support the effectiveness of antipsychotics, there have been some vigorous challenges to their usefulness. David Healy (2012) has suggested that some successful trials have had their data published multiple times, exaggerating the evidence for positive effects. Healy also suggests that because antipsychotics have powerful calming effects, it is easy to demonstrate that they have some positive effect on patients. This is not the same as saying they really reduce the severity of psychosis. To make matters worse, most published studies assess short-term benefits rather than long-term benefits and compare patients who keep taking antipsychotics with those suffering withdrawal having just stopped taking them.

Question 21

Evaluation
The chemical cosh argument

Answer 21

It is widely believed that antipsychotics have been used in hospital situations to calm patients and make them easier for staff to work with, rather than for the benefits to the patients themselves. Although short-term use of antipsychotics to calm agitated patients is recommended by the National Institute for Health and Clinical Excellence (NICE), this practice is seen by some as a human rights abuse (Moncrieff 2013).

Question 22

Evidence for Effectiveness:

Ben Thornley et al. (2003)

Answer 22

A large body of evidence supports the effectiveness of both typical and atypical antipsychotics in managing symptoms of schizophrenia. For example, Ben Thornley et al. (2003) found that Chlorpromazine improved functioning and reduced symptoms in a study with 1121 participants.

Question 23

Strength of Evidence for Chlorpromazine:

Ben Thornley et al. (2003)

Answer 23

In a review by Ben Thornley et al. (2003), data from 13 trials showed that Chlorpromazine was linked to better overall functioning, and from three trials, a lower relapse rate when compared to placebo.

Question 24

Effectiveness of Clozapine:

Answer 24

Herbert Meltzer (2012) concluded that Clozapine is more effective than typical antipsychotics and is effective in 30-50% of treatment-resistant cases where typical antipsychotics failed.

Question 25

Inconclusive Results for Drug Comparisons:

Answer 25

Studies comparing Clozapine and Risperidone have shown inconclusive results, possibly due to individual differences in how patients respond to different drugs.

Question 26

General Effectiveness of Antipsychotics:

Answer 26

Overall, antipsychotics are reasonably effective in treating schizophrenia, which is a strength of these medications.

Question 27

Serious Side Effects:

Answer 27

A major issue with antipsychotic drugs is the potential for side effects ranging from mild to serious, and even fatal.

Question 28

Side Effects of Typical Antipsychotics:

Answer 28

Typical antipsychotics cause side effects such as dizziness, agitation, sleepiness, stiff jaw, weight gain, and itchy skin. Long-term use can cause tardive dyskinesia, which results in involuntary facial movements.

Question 29

Most Serious Side Effect:

Answer 29

Neuroleptic malignant syndrome (NMS) is the most serious side effect of typical antipsychotics. It can lead to high temperature, delirium, coma, and death.

Question 30

Frequency of NMS:

Answer 30

Estimates of NMS frequency range from less than 0.1% to just over 2%, but it has become rarer as typical doses of antipsychotics have declined.

Question 31

Atypical Antipsychotics and Side Effects:

Answer 31

Atypical antipsychotics were designed to reduce the frequency of side effects, and this has generally been successful, though side effects still remain.

Question 32

Clozapine and Blood Monitoring:

Answer 32

Patients on Clozapine must have regular blood tests to detect early signs of agranulocytosis, a serious side effect.

Question 33

Side Effects Remain a Significant Weakness:

Answer 33

Despite the development of atypical antipsychotics, side effects continue to be a major weakness of antipsychotic drugs.

Question 34

Dopamine Hypothesis and Antipsychotics:

Answer 34

The use of antipsychotics is based on the dopamine hypothesis, which suggests that schizophrenia is linked to higher-than-normal dopamine levels in the subcortex of the brain.

Question 35

Dopamine Hypothesis and Its Limitations:

Answer 35

Evidence suggests the original dopamine hypothesis is not fully accurate, as dopamine levels in parts of the brain other than the subcortex may actually be too low.

Question 36

Uncertainty About How Antipsychotics Work:

Answer 36

If dopamine levels are low in other parts of the brain, it is unclear how antipsychotics, which reduce dopamine activity, can help alleviate schizophrenia symptoms.

Question 37

Criticism of Antipsychotic Effectiveness:

Answer 37

The relationship between dopamine and psychosis has led some to doubt the effectiveness of antipsychotics, undermining confidence in their use.