biological approach- ECT and chemotherapy
- example- chlorpromazine- used primarily to combat pymptoms of scizophrenia.
- block the action of the neurotransmitter dopamine in the brain by binding to but not stimulating dopamine receptors.
- atpical antipsychotic drugs e.g clozapine act by only temporarily occupying dopamine receptiors and then rapidily dissociating to allow normal dopamine transmission- explain why sycg atypical antipsychotics have lower levels of side effects e.g involuntary movements of the mouth.
- depression is thought to be due to insufficent amounts of neurotransmitters e.g serotonin being produced in the nerve endings. normal- neurotransmitters are constantly being released from the nerve endings stimulating the neibouring neurons. to terminate thier action, neurotransmitters are reabsorbed into the nerve endings or broken down by enzymes.
- antidepressants work either by reducing the rate of reabsorbtion or by blocking the enzyme which breaks down the neurotransmitters. both of these mechanisms increase the amount of neurotransmitters available to excite cells.
- most common is SSRI's-work by blocking the transporter mechanism that re-absorbs serotonin ito the presynaptic cell after it has fired= more serotonin left in synapse prolonging its activity and making trnasmission of next impulse easier.
strengths and limitations of chemotherapy
effectiveness- research evidence proves it does work- WHO. reported that relapse rates after 1yr were highest 55%- when schizophrenics were treated with placebos - 25% with antipshychotic drugs along and 2%-23% when antipsychotic was combined with family intervention- suggeststhat drugs play an important role although treatment combined with psychological support.
ease of use-
required little effort from the user to use chemotherapy than for therapies such as pshychoanalysis- however many clinicians advocatea mixture of chemotherapy and form of psychotherapy- comer 2002.
- psychological effect as well as the chemical effect- kirsch 2002 reviewed 28 studies of antidepressants and found that patients who received placebos fared almost as well as those getting real drugs- other reviews have found stronger effects for the real drugs. Mulrow 200 compared the use of tricyclics and placebos in 28 studies and found a succes rate of 35% for placebos and 60% for tricyclics.
SSRI's may cause anxiety,nausea and suicidal thoughts- no. of court cases have held drug companies responsible for failing to inform patients about potenital aggressive tendencies- e.g US in 1998 Schell 60 killed his wife daughter and grandaughter and then himself after 2 days on an SSRI- drug company was sued- they won- side effects can lead patients deciding not to take thier medication.