Biological Treatments for Schizophrenia – Drug Therapy
The biological treatments for schizophrenia are based on the use of antipsychotics. These are
psychotropic drugs (given for mental disorders) which try to reduce the symptoms of
schizophrenia, especially the positive symptoms such as hallucinations and delusions. These
drugs can be taken as tablets, syrup or as injections for clients who are at risk of failing to take
their medication. Some clients may only take a short course of antipsychotics and never
experience any further symptoms. However, schizophrenia is often experienced as a sequence of
relapse and remission and some clients may need to take antipsychotics for long periods / for life
to prevent or reduce the likelihood of psychotic episodes.
There are two types of drug:
Typical antipsychotics
These are older drugs. They were the “first generation” of antipsychotics and were developed in
the 1950s. They are linked to the dopamine hypothesis, that schizophrenia is caused by high
levels of dopamine activity in the sub-cortex. Typical antipsychotics are dopamine antagonists
like Chlorpromazine which reduce the activity of dopamine by blocking (binding to but not
stimulating) dopamine receptors at the postsynaptic neuron. They are fundamentally aimed at
preventing/reducing the positive symptoms of schizophrenia such as hallucinations and
delusions. Chlorpromazine is also often an effective sedative and is sometimes used to treat
distressed clients, e.g. on arrival in a mental hospital after being sectioned.
The positive symptoms of schizophrenia are associated with dopamine activity in one area of
the brain (the mesolimbic pathway), but typical antipsychotics block dopamine receptors in
other dopamine pathways in other parts of the brain too. This leads to the serious side effects of
typical antipsychotics such as tardive dyskinesia. The severity of these side effects and the fact
that so many people suffered from them led to the development of atypical antipsychotics.
Atypical antipsychotics
These are newer drugs. They are the “second generation” of antipsychotics as they were
developed more recently and include drugs like Clozapine (1970s) and Risperidone (1990s).
Clozapine was more effective than the typical antipsychotics but caused a blood condition called
agranulocytosis which proved fatal for some clients. It is still used today but clients need to take
blood tests, and it is not given as an injection. Clozapine binds to dopamine receptors but also
acts on other neurotransmitters such as serotonin and glutamate. Risperidone was intended to
match the effectiveness of Clozapine but avoid its side effects. Risperidone also binds to
dopamine and serotonin receptors but much more strongly, so usage levels are far lower than for
the early typical antipsychotics. Reducing side effects whilst retaining similar levels of
, effectiveness was a key reason for the development of the second-generation atypical
antipsychotics.
Therefore, atypical antipsychotics are different to typical antipsychotics in five main ways:
- They target a range of neurotransmitters including dopamine and serotonin (rather than
just dopamine)
- Like typical antipsychotics, atypical antipsychotics also treat the positive symptoms of
schizophrenia but there is some evidence that they also have beneficial effects on the
negative symptoms of schizophrenia too.
- They are suitable for “treatment resistant” clients (i.e. clients prescribed typical
antipsychotics but didn’t benefit from them)
- Atypical antipsychotics have less side effects than typical antipsychotics, particularly in
terms of problems with movement
- Atypical antipsychotics only occupy the dopamine receptors and block dopamine
transmission for a brief amount of time. This is known as “rapid dissociation”, and it
enables dopamine transmission to quickly return to normal.
‘Discuss drug therapy in the treatment of schizophrenia (16 marks)’
Model answer
The biological treatments for schizophrenia are linked to the dopamine hypothesis as a cause of
schizophrenia and are based on the use of antipsychotics. As schizophrenia is often experienced as an
episodic sequence of relapse and remission, some clients may need to take antipsychotics for long periods
to prevent or reduce the likelihood of psychotic episodes.
Typical antipsychotics like Chlorpromazine were the “first generation” of antipsychotics to be developed.
They are dopamine antagonists which reduce the activity of dopamine by blocking (binding to but not
stimulating) dopamine receptors at the postsynaptic neuron. They target the positive symptoms of
schizophrenia such as hallucinations and delusions.
Atypical antipsychotics like Clozapine and Risperidone are the “second generation” of antipsychotics.
Atypical antipsychotics are different to typical antipsychotics in five main ways: they target a range of
neurotransmitters including serotonin as well as dopamine, there is some evidence that they also have
beneficial effects on the negative symptoms of schizophrenia, they are suitable for “treatment resistant”
clients, have less side effects, particularly in terms of problems with movement, and only occupy the
dopamine receptors and block dopamine transmission for a brief amount of time. This is known as
“rapid dissociation”, and it enables dopamine transmission to quickly return to normal.
A03
The biological treatments for schizophrenia are based on the use of antipsychotics. These are
psychotropic drugs (given for mental disorders) which try to reduce the symptoms of
schizophrenia, especially the positive symptoms such as hallucinations and delusions. These
drugs can be taken as tablets, syrup or as injections for clients who are at risk of failing to take
their medication. Some clients may only take a short course of antipsychotics and never
experience any further symptoms. However, schizophrenia is often experienced as a sequence of
relapse and remission and some clients may need to take antipsychotics for long periods / for life
to prevent or reduce the likelihood of psychotic episodes.
There are two types of drug:
Typical antipsychotics
These are older drugs. They were the “first generation” of antipsychotics and were developed in
the 1950s. They are linked to the dopamine hypothesis, that schizophrenia is caused by high
levels of dopamine activity in the sub-cortex. Typical antipsychotics are dopamine antagonists
like Chlorpromazine which reduce the activity of dopamine by blocking (binding to but not
stimulating) dopamine receptors at the postsynaptic neuron. They are fundamentally aimed at
preventing/reducing the positive symptoms of schizophrenia such as hallucinations and
delusions. Chlorpromazine is also often an effective sedative and is sometimes used to treat
distressed clients, e.g. on arrival in a mental hospital after being sectioned.
The positive symptoms of schizophrenia are associated with dopamine activity in one area of
the brain (the mesolimbic pathway), but typical antipsychotics block dopamine receptors in
other dopamine pathways in other parts of the brain too. This leads to the serious side effects of
typical antipsychotics such as tardive dyskinesia. The severity of these side effects and the fact
that so many people suffered from them led to the development of atypical antipsychotics.
Atypical antipsychotics
These are newer drugs. They are the “second generation” of antipsychotics as they were
developed more recently and include drugs like Clozapine (1970s) and Risperidone (1990s).
Clozapine was more effective than the typical antipsychotics but caused a blood condition called
agranulocytosis which proved fatal for some clients. It is still used today but clients need to take
blood tests, and it is not given as an injection. Clozapine binds to dopamine receptors but also
acts on other neurotransmitters such as serotonin and glutamate. Risperidone was intended to
match the effectiveness of Clozapine but avoid its side effects. Risperidone also binds to
dopamine and serotonin receptors but much more strongly, so usage levels are far lower than for
the early typical antipsychotics. Reducing side effects whilst retaining similar levels of
, effectiveness was a key reason for the development of the second-generation atypical
antipsychotics.
Therefore, atypical antipsychotics are different to typical antipsychotics in five main ways:
- They target a range of neurotransmitters including dopamine and serotonin (rather than
just dopamine)
- Like typical antipsychotics, atypical antipsychotics also treat the positive symptoms of
schizophrenia but there is some evidence that they also have beneficial effects on the
negative symptoms of schizophrenia too.
- They are suitable for “treatment resistant” clients (i.e. clients prescribed typical
antipsychotics but didn’t benefit from them)
- Atypical antipsychotics have less side effects than typical antipsychotics, particularly in
terms of problems with movement
- Atypical antipsychotics only occupy the dopamine receptors and block dopamine
transmission for a brief amount of time. This is known as “rapid dissociation”, and it
enables dopamine transmission to quickly return to normal.
‘Discuss drug therapy in the treatment of schizophrenia (16 marks)’
Model answer
The biological treatments for schizophrenia are linked to the dopamine hypothesis as a cause of
schizophrenia and are based on the use of antipsychotics. As schizophrenia is often experienced as an
episodic sequence of relapse and remission, some clients may need to take antipsychotics for long periods
to prevent or reduce the likelihood of psychotic episodes.
Typical antipsychotics like Chlorpromazine were the “first generation” of antipsychotics to be developed.
They are dopamine antagonists which reduce the activity of dopamine by blocking (binding to but not
stimulating) dopamine receptors at the postsynaptic neuron. They target the positive symptoms of
schizophrenia such as hallucinations and delusions.
Atypical antipsychotics like Clozapine and Risperidone are the “second generation” of antipsychotics.
Atypical antipsychotics are different to typical antipsychotics in five main ways: they target a range of
neurotransmitters including serotonin as well as dopamine, there is some evidence that they also have
beneficial effects on the negative symptoms of schizophrenia, they are suitable for “treatment resistant”
clients, have less side effects, particularly in terms of problems with movement, and only occupy the
dopamine receptors and block dopamine transmission for a brief amount of time. This is known as
“rapid dissociation”, and it enables dopamine transmission to quickly return to normal.
A03
