9. Biological treatments for schizophrenia

What are some first generation/typical antipsychotics?

• Chlorpromazine.

• Fluphenazine.

• Haloperidol.

• Perphenazine.

What are some second generation/atypical antipsychotic drugs

• Aripiprazole (Abilify).

• Asenapine (Saphris).

• Brexpiprazole (Rexulti).

• Cariprazine (Vraylar)

How is schizophrenia treated?

• There is no cure.

• All we can do is treat the symptoms to improve the quality of life for sufferers.

• The aim is to make the symptoms more manageable and if the symptoms are under control, this makes other forms of treatment easier to access.

• original drugs used in the 1950’s (first generation drugs) had some nasty side effects and so led to the development of ‘atypical’ antipsychotics such as clozapine which had less side effects.

• Whichever drug is prescribed, they all work in the same way to reduce dopamine in the brain by blocking dopamine receptors (antagonist).

• This will result in a reduction in positive symptoms.

What are the two main dopamine pathways in the brain?

How to antipsychotic drugs work?

• The two main dopamine pathways in the brain are:

• The mesolimbic pathway which is hyperactive/excess dopamine and causes positive symptoms e.g. delusions, hallucinations, disorganised thoughts.

• And the mesocortical pathway which has too little dopamine causing negative symptoms e.g. apathy, avolition, social withdrawal.

• Antipsychotic drugs act on the neurotransmitter dopamine.

• Within the dopamine pathways D2 receptors have been identified as being involved in the development of schizophrenia and they are the main targets of antipsychotic drugs.

• Antipsychotic drugs can be grouped into typical (1st gen) and atypical (2nd gen).

• For typical drugs their only aim is to block D2 receptors.

How do first generation/typical antipsychotic drugs work?

• Typical drugs are antagonists, they block D2 receptors all over the dopamine pathways.

• Reduction of dopamine in the mesolimbic pathway reduces the positive symptoms.

• However if we are blocking the receptors in the mesocortical pathways that are already deficient in dopamine it is going to make the negative symptoms even worse - even less emotional expression, social interaction, motivation.

What are examples of typical antipsychotics?

• High potency - Haloperidol.

• Low potency - Chlorpromazine

How does Meltzer’s (2014) research show the effectiveness of typical drugs?

• Research A03

• Meltzer tested the difference between the effectiveness of typical, atypical antipsychotics , and a placebo.

• He found that after 6 weeks, patients taking haloperidol, or clozapine had reduced symptoms.

• Patients taking the placebo shown the same symptoms/no difference.

• Atypical and typical drugs are effective in treating symptoms.

How does Liebermann’s (2005) research show a weakness of typical drugs in terms of side-effects?

• Research A03

• Liebermann’s research has found that many patients will stop taking their medication because of severe side effects, which has serious consequences for the effectiveness of this treatment.

What is a weakness of typical drugs in terms of side effects?

• A03

• The stronger the typical antipsychotics, cause the more severe side effects.

What is a weakness of typical antipsychotics in terms of a specific side effect?

• A03

• Typical antipsychotics are also associated with disturbances of movement and posture such as tremors and muscle spasms.

• Patients who use typical antipsychotics in the long term can end up with a condition called ‘tardive dyskinesia’ - which causes involuntary muscle spasms that commonly occur around the mouth and can affect speech, but which can be irreversible.

How do second generation/atypical antipsychotic drugs work?

• Atypical drugs are still antagonists and block D2 receptors for dopamine.

• Also block serotonin receptors.

• Serotonin effects the levels of dopamine - when blocking serotonin the levels of dopamine increase in certain areas of the brain (mesocortical).

What are examples of atypical antipsychotics?

• Clozapine.

• Olanzapine.

How does Brar’s (1997) research show the effectives of clozapine/atypical?

• Research A03

• One of these drugs clozapine has been shown to be highly effective in treating the positive symptoms of hallucinations and other associated psychotic symptoms including some negative symptoms such as emotional withdrawal, even in people who have not previously responded to treatment with other drugs.

How does Seeman’s (2002) research show the effectiveness of atypical drugs in terms of how they can be taken?

• Research A03

• These drugs can be given in tablet form, or in some cases they can be administered by injections by a nurse, especially if there is a risk that the patient will not comply with the treatment regimen themselves.

How does Lieberman’s (2005) research show a weakness of atypical drugs in terms of side effects?

• Research A03

• Lieberman’s research has found that many patients will stop taking their medication because of severe side effects, which has serious consequences for the effectiveness of this treatment.

How does Meltzer’s (2014) show the effectiveness of atypical antipsychotics?

• Meltzer tested the difference between the effectiveness of typical, atypical antipsychotics and a placebo.

• He found that after 6 weeks, patients taking haloperidol, or clozapine had reduced symptoms.

• Patients taking the placebo shown the same symptoms/no difference.

• Atypical and typical drugs are effective in treating symptoms.

How does McEvoy’s (2006) research show the effectiveness of clozapine/atypical?

• Research A03

• McEvoy compared the time taken to discontinue treatment with 4 atypical drugs.

• The patients had already stopped taking another atypical drug earlier on in their treatment because the drugs were not working.

• They found that of the 4 drugs that were offered to the patient group to try, the most effective was clozapine because patients in this group continued taking this drug considerably longer than any of the others.

• The assessment of symptoms taken after 3 months of taking the new drug also showed the most improvement in the group taking clozapine.

• Also effective at reducing positive and negative symptoms.

What is a strength of atypical drugs in terms of side effects?

• A03

• The atypical drugs seem to have fewer reported side effects while still being effective, making them preferable for many patients.

• They also reduce the negative symptoms and the positive symptoms.

What is a weakness of atypical antipsychotics in terms of side effects still being there?

• A03

• Atypical antipsychotics still have some side effects although not as severe as typical drugs.

• Atypical antipsychotics have reported side effects such as weight gain and metabolic changes which could increase risk of diabetes and high cholesterol.

• Side effects such as weight gain, dryness of the mouth, sleep problems.

What is a weakness of clozapine/atypical?

• A03

• Clozapine can cause a serious condition called agranulocytosis - when the bone marrow does not produce enough white blood cells, the immune system is effected.

• Patients must go for regular blood tests.

What are the evaluation points in terms of Ethics for this biological treatment?

• Synoptic A03

• If a patient is detained under section 3 of the Mental health act, treatment can be given without their consent if it is deemed necessary.

• Drug therapy is one of the only treatments that can be given in this way and some would argue that this breaches ethical guidelines.

• However, for treatment to be given without consent, the patient’s current state of mind must be considered, that is if they are putting themselves or others in danger.

• In fact, in some cases, it could be argued that the patient’s symptoms could mean they are unable to know what is best for them and so receiving treatment forcibly may be the most positive course of action.

What are the evaluation points in terms of Social control for this biological treatment?

• Synoptic A03

• There is a great deal of debate over whether some forms of medication have sometimes been used to make patients with abnormal behaviour more manageable.

• Many of the older, typical psychotic drugs made patients very passive and therefore easier for staff in institutions to control, which may have made the drugs open to abuse in busy wards.

• As such, drug treatments that have these effects have been regarded as a chemical straightjacket.

• There is also a lot of opposition to the use of drugs to treat mental illness because pharmaceutical companies are argued to be more interested in making money from the drugs they produce rather than actually helping the patients who take them.

• More should be done to help treat patients long term and help them avoid side effects associated with the use of antipsychotic drugs.

What are the evaluation points in terms of Psychological knowledge overtime for this biological treatment?

• Synoptic A03

• Typical drugs had much more severe side effects and were less effective in treating schizophrenia.

• Typical drugs only dealt with positive symptoms - even worsened negative symptoms.

• Atypical drugs were created which have much less severe side effects and treat both positive and negative symptoms.