Biological Treatments PDF

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Biological treatments...

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(For an 8 marker you’d use the structure of one of these e. g typical or atypical, for a 16 marker both but not all evaluation points need to be included) Side effects, effectiveness, methodological and ethical issues and research against and research supporting. Introduction: Prior to the introduction of antipsychotic drugs in the 1950’s, there was no effective treatment for SZ. Until this time the standard treatment was a long term stay in a psychiatric hospital and hoping for some improvements’ in symptoms. Following the discovery of dopamine drugs were developed that had a direct impact on this neurotransmitter. Some of these drugs reduced symptoms in people who were severely ill. Drugs that had this effect became known as antipsychotics and were used in drug therapy. Most drugs tend to be palliative, this means that they don’t cure the illness, just relive its symptoms, it’s a short term solution. Antipsychotics are drugs that are most effective in treating the most disturbing forms of psychotic illness e.g manic depression and SZ. Antipsychotics are usually recommended as the initial treatment for symptoms of sz, after which clinicians use a combination of medication and psychological therapies. Drugs are therefore important in order to enable the therapy. All antipsychotics work by reducing dopaminergic transmission. The two types of antipsychotics are typical and atypical. Typical antipsychotics (1st generation): The first type of antipsychotics is typical antipsychotics. These are used primarily to combat the positive symptoms such as hallucinations and though disturbances- products of an over reactive dopamine system. The mode of action of typical antipsychotics is to reduce the effects of dopamine and so reduce the symptoms. Typical antipsychotics are dopamine antagonists in that they bind to but do not stimulate dopamine receptors. By recuing stimulation of the dopamine system in the mesolimbic pathway, antipsychotic drugs such as Pimozide eliminate hallucinations and delusions experienced by people with the disorder. Hallucinations and delusions usually diminish within a few days beginning medication, although symptoms can take several weeks before significant improvements’ are noted. The effectiveness of dopamine antagonists in reducing these symptoms led to development of dopamine hypothesis. Kapur et al (200) estimated that 60% to 75% of D2 receptors in the mesolimbic pathway must be blocked for these drugs to be effective. Typical antipsychotics often have serious side effects, this is because they mode of action is to block all dopamine receptors, this is a problem because everyone needs some dopamine e.g. to show emotion- taking it all away could cause more problems than it solves. Side effects are often reduced by reducing the dosage until the side effects disappear or by using other drugs to control side effects. This issue has been addressed by newer atypical antipsychotics. Name of Typical Antipsychotic:

PIMOZIDE

Mode of Action

Works by blocking the action of Dopamine, a naturally occurring chemical in the brain.

Dosage

Usual daily dose: 4-20mg// Max daily dose: 20 mg.

Common Side effects

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Constipation Drowsiness Restlessness Dry mouth

Severe side effects

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Fainting Blurred vision/ rigid muscles Uncontrolled muscle spasms Decreased sexual desire Inability to move eyes

Research to support effectiveness

Evaluation: research support Support for effectiveness of antipsychotics such as typical drugs comes from studies that have compared relapse rates for antipsychotics like Pimozide and placebos. Leucht et al (2012) carried out a meta analysis of 65 studies published between 1959 and 2011, involving nearly 6000 patients all patients had been stabilised on either typical drugs or atypical. Some of these patients were taken of drugs and given a placebo instead, the remaining patients remained on their regular drugs. Within 12 months, 64% of those given placebos had relapsed compared to 27% who stayed on the antipsychotic drug. Evaluation: side effect and ethical issue Typical antipsychotic cause side effects that can be very distressing to the patient. This can cause movement problems called extra pyramidal effects, because they affect the extra pyramidal area of the brain, which helps control motor activity. Many patients therefore resemblance the features of Parkinson’s disease. When drugs are taken for an extended period, it can lead to a second type of extra pyramidal effect i.e. involuntary movements of the tongue, jaw and face. More than half of patients experience distressing side effects like this. This means additional drugs may have to be given to control them, and on most occasions the individual has no choice but to take them in order to make them feel better. As a result could lead to mental health problems among patients who want to regain control of some aspects of their lives e.g. depression and anorexia. This has a further effect on treatment and diagnosis, due to the issue of co-morbidity it could lead to misdiagnosis. Ultimately these side effects are so distressing for the patient they may stop taking the drugs. Evaluation: research against Hogarty et al (1986) assessed relapse rated in 103 schizophrenics from high expression emotion families receiving various treatments, finding first year relapse rates to be 91% for fam therapy and

drugs, 20% for social support and drugs, and 41% for drugs alone. This suggests that drugs alone are not effective enough in treating SZ.

Evaluation:

Atypical antipsychotics (2nd generation): So called because of three main differences to typical drugs: they carry a lower risk of extra pyramidal side effects, have a beneficial effect on negative symptoms and cognitive impairment, and are suitable for treatment resistant patients. As with typical drugs, they mode of action is to block D2 receptors in order to impact the dopamine system. However, they only temporarily block /occupy the D2 receptors and then rapidly dissociate to allow normal dopamine transmission. In addition they also block serotonin receptors 5(H-T). This means that they are less dangerous and hence fewer side effects because they still allow healthy amounts of dopamine. Because atypical drugs, such as Clozapine have very little effect on the dopamine systems that control movements, they tend not to cause the movement problems found with typical antipsychotics. Name of Atypical Antipsychotic:

CLOZAPINE

Mode of Action

Binds to serotonin as well as dopamine receptors. Clozapine is a partial agonist at the 5-HT1A subunit of the serotonin receptor. Improving depression, anxiety and cognitive symptoms associated with SZ. Acts on serotonin as well as dopamine production systems, affecting negative symptoms of the disorder e.g emotional expression- however it is not known exactly how they relieve symptoms.

Dosage

Usual daily dose: 200-450mg// Max daily dose: 900 mg.

Common Side effects

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Hypotension/fever Headache/nausea/vomiting/constipation Weight gain Dizziness

Severe side effects

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Sudden jerky movements of the body Yellow eyes Uncontrolled chewing movements Sudden shortness of breath

Research to support

Murder (1996) reported atypical antipsychotic Clozapine is as

effectiveness

effective in relieving the positive symptoms of SZ, and in effect in approx 30-61% of patients who are resistant to typical antipsychotics, suggesting it to be a more superior form of treatment.

Evaluation: research against& side effect The introduction of atypical antipsychotics led to claims of the superiority of these drugs over ‘typical’ ones. Crossley et al (2010) carried out a Meta analysis for 15 studies to examine the efficacy and side effects of atypical vs typical drug the early phase treatment of SZ. They found no significant difference between typical and atypical in terms of the effect on symptoms, but did note differences in side effects experiences. Patients on atypical drugs gained more weight than those on typical, whereas those on typical experienced more extra pyramidal side effects. They concluded there was no evidence for differences in efficiency between the two, but there was a clear difference in side effect profile. Evaluation: ethical issues Ross and read (2004) argue that when people are prescribed antipsychotic medication, it reinforces the view that ‘something’s wrong with them’. His prevents the individual from thinking about possible stressors (such as life history or current circumstances) that might be possible for their condition. In turn this reduces their motivation to look for possible solutions that might alleviate these stressors and reduce their suffering. In fact a number of international surveys have shown that the public when asked what causes SZ, cite social factors such as poverty or traumatic childhoods, far more often than biological factors (read and Haslam, 2004). Evaluation: methodological issues Atypical cost about £75 per prescription compared with only £17 for typical drugs, and research has not yet backed up claims that they are more effective. Although they reduce side effects associated with typical drugs, they incur serious side effect risks on their own, which drug companies were not keen to admit. The Johnson and Johnson pharmaceutical company were fined $2.2 billion, after allegations of ‘purposely withholding findings’ about antipsychotics it sold increasing risk of strokes, diabetes and being associated with breast growth in men. Evaluation: research support

Evaluation: Turkington at al argues that there is a good logical fit between the integrationist approach and combination treatment. However juts because combined treatment works not mean the integrationist treatment is correct. Similarly just because drugs help does not mean that SZ is biological in origin. This error of logic is called the treatment-causation fallacy.

Conclusion: In conclusion, atypical drugs generally seen more effective than typical drugs. However no one drug can be considered superior in terms of side effects, symptom reduction and cost-effectiveness. Different schizophrenics have different symptoms, and different experiences, so we cannot say everyone will react to treatments in the same way. This means that different drugs suit different patients better, though this can be determined only be trial and error. Ultimately this means that the cause of SZ is different for each individual, no one universal cause or treatment....