The word ‘chemotherapy’ is more frequently heard in the context of cancer treatment. However the word refers to all forms of chemical or drug treatment.
Drug treatments for mental illness can be classified into 4 main types:
- Antidepressant drugs
- Anti-psychotic drugs (neuroleptics)
- Anti-manic drugs
- Anti-anxiety drugs (anxiolytics)
Antidepressants (stimulants) are mainly used to treat the symptoms of depression, but are also used to treat agoraphobia and eating disorders. They do not address the cause of the problem in reactive depression such as loss or bereavement.
There are three categories of anti-depressants: tricyclics, MAOI therapy (Monoamine Oxidase Inhibitors) and tetracyclics (serotonin re-uptake inhibitors). These work in slightly different ways but all have the general effect of increasing the availability of the neurotransmitters norepinephrine and serotonin. The most widely-known among these is the tetracyclic drug Prozac.
Short courses of antidepressant drugs can be very worthwhile in cases of severe clinical depression. Without them, patients often have no motivation to engage in psychological treatment. Antidepressants are often essential as a first treatment because of the high risk of suicide in depressed patients. Antidepressants have been tested in trials with placebos and found to be effective in reducing symptoms of severe depression in 65 to 75% of cases, compared to 33% for placebos (Spiegal, 1989).
Again, there are a number of physical side effects. Blurred vision, hallucinations, heart problems, hypertension, dizziness, fatigue, nausea, and anxiety have all been evidenced. Prozac is currently the most frequently prescribed antidepressant. It was hailed as a 'wonder drug' when it was first introducedin the late 1980s, though more recently, side effects such as preoccupations with violence and suicide have been noted (Steiner, 1991).
Anti-psychotic drugs: Neuroleptics
Neuroleptics are used mainly to treat schizophrenia but also other severe disorders including mania and amphetamine abuse. The most widely used group is phenothiazines.
Introduced in the 1950s, phenothiazines are major tranquillisers which sedate the patient and ameliorate symptoms of psychosis such as delusions and hallucinations. They were a revolution in the treatment of psychotic individuals as for the first time they offered an alternative to physical restraints such as straitjackets and cool baths. Previously schizophrenics were considered untreatable and interned in mental hospitals.
These drugs have enabled many patients to live a normal life within the community. In 1997, the American Psychiatric Association reported that phenothiazines are effective with 60% of patients. However, 'effectiveness' is relative - neuroleptics do not actually cure schizophrenia, although they do reduce its prominent symptoms (Hutton, 1998), and are of little value in treating social difficulties. It is estimated that around seven percent of people diagnosed with schizophrenia refuse to take phenothiazines (Hoge et al. 1990).
However, there are drawbacks. Research indicates that if medication is stopped abruptly and too soon, then symptoms reoccur (Davis et al., 1993). This has lead to the 'revolving door syndrome' of continual discharge into the community and readmission into hospital. Also, it is thought that phenothiazines destroy a part of the brain, and that once begun, this process is irreversible. This occurs in around 30% of those taking the drug and the risk increases with prolonged usage (Gualtieri, 1991).
As with most drug treatments for mental illness, tremors are noted as a potential side effect. Among the many other possible physical side effects are a number involving loss of control of movement: epileptic seizures, spasms and muscle contractions, immobility of face, tardive dyskinsia, fidgeting, and a shuffling gait. Blurred vision, agitation, low blood pressure, irregular heartbeat and grogginess may also be experienced.
Antimanics are lithium salts used to control the mania in those suffering from manic depression and became routine treatment for manic depression in the 1970s.
The precise mode of action of lithium salts is not known. It is likely that they decrease the availability of the neurotransmitters noradrenaline and serotonin by increasing the re-uptake of these from the synapses between neurons.
Lithium salts have been found to be effective for 80% of patients with manic depression (Rosenhan and Seligman, 1995). Improvements in mood are usually evident within two weeks of starting treatment. Prior to the introduction of lithium salts, 15% of manic-depressives committed suicide and a large proportion were unable to function properly in daily life because of their mood swings.
Nevertheless, there are drawbacks. A study carried out over a period of five years suggests that 70% of people relapse while on medication (Gitlin et al., 1995), and many potential patients choose not to take lithium at all as they enjoy being in a euphoric state (Johnson et al., 1989).
Lithium salts flatten out cycles of manic behaviour. Once the manic phase in bipolar disorder has been eliminated, the depressed phase does not return.
Anti-anxiety drugs: anxiolytics
Anxiolytics, known as benzodiazepines, are minor tranquillizers designed to reduce levels of anxiety.
One of the main problems with anxiolytic drugs is that they only treat the physical symptoms and not the cause of the anxiety. This is illustrated by a medical study in which the results suggested a 90% relapse rate when benzodiazepine medication is ceased (Fryer et al. 1987).
Benzodiazepines become less potent over time as the body builds up tolerance and requires larger doses which can lead to physical dependency on the drug. Dependency also leads to physical withdrawal symptoms, such as delirium, irritability and insomnia. Other side effects include increased sweating, problems with concentration, lack of co-ordination, drowsiness, and depression.
Benzodiazepines were frequently prescribed by GPs in the 1960s and 1970s but a quick and easy solution created a dependency on the drug which could remain years after the initial problem had been resolved. In recent years self-help groups have been developed for people trying to overcome their long-term dependence.