Biomedical therapies include drug therapy, electroconvulsive therapy, and psychosurgery.
Drug therapy, or psychopharmacotherapy, aims to treat psychological disorders with medications. Drug therapy is usually combined with other kinds of psychotherapy. The main categories of drugs used to treat psychological disorders are antianxiety drugs, antidepressants, and antipsychotics.
Antianxiety drugs include a class of drugs called benzodiazepines, or tranquilizers. Two commonly used benzodiazepines are known by the brand names Valium and Xanax. The generic names of these drugs are diazepam and alprazolam, respectively:
- Effects: Benzodiazepines reduce the activity of the central nervous system by increasing the activity of GABA, the main inhibitory neurotransmitter in the brain. Benzodiazepines take effect almost immediately after they are administered, but their effects last just a few hours. Psychiatrists prescribe these drugs for panic disorder and anxiety.
- Side effects: Side effects may include drowsiness, light-headedness, dry mouth, depression, nausea and vomiting, constipation, insomnia, confusion, diarrhea, palpitations, nasal congestion, and blurred vision. Benzodiazepines can also cause drug dependence. Tolerance can occur if a person takes these drugs for a long time, and withdrawal symptoms often appear when the drug use is discontinued.
Antidepressants usually take a few weeks to have an effect. There are three classes of antidepressants: monoamine oxidase inhibitors, tricyclics, and selective serotonin reuptake inhibitors.
- Monoamine oxidase inhibitors (MAOIs): Include phenelzine (Nardil).
- Tricyclics: Include amitriptyline (Elavil). Tricyclics generally have fewer side effects than the MAOIs.
- Selective serotonin reuptake inhibitors (SSRIs): The newest class of antidepressants, including paroxetine (Paxil), fluoxetine (Prozac), and sertraline (Zoloft).
Antidepressants are typically prescribed for depression, anxiety, phobias and obsessive-compulsive disorder.
- Effects: MAOIs and tricyclics increase the level of the neurotransmitters norepinephrine and serotonin in the brain. SSRIs increase the level of serotonin.
- Side effects: Although antidepressants are not addictive, they often have side effects such as headache, dry mouth, constipation, nausea, weight gain, and feelings of restlessness. Of the three classes of antidepressants, MAOIs generally have the most side effects. People who take MAOIs also have to restrict their diet, because MAOIs interact negatively with foods that contain the amino acid tyramine, such as beer and some cheeses and meats. SSRIs have fewer side effects than the other two classes of antidepressants. However, SSRIs can cause sexual dysfunction, and if they are discontinued abruptly, withdrawal symptoms occur.
Antipsychotic drugs are used to treat schizophrenia and other psychotic disorders. They include chlorpromazine (Thorazine), thioridazine (Mellaril), and haloperidol (Haldol). Antipsychotic drugs usually begin to take effect a few days after they are administer ed.
- Effects: Antipsychotic drugs, or neuroleptics, reduce sensitivity to irrelevant stimuli by limiting the activity of the neurotransmitter dopamine. Many antipsychotic drugs are most useful for treating positive symptoms of schizophrenia, such as hallucinations and delusions. However, a new class of antipsychotic drugs, called atypical antipsychotic drugs, also help treat the negative symptoms of schizophrenia. They reduce the activity of both dopamine and serotonin. Atypical antipsychotic drugs include clozapine (Clozaril), olanzapine (Zyprexa), and quetiapine (Seroquel). Atypical antipsychotic drugs can sometimes be effective for schizophrenia patients who have not responded to the older antipsychotic drugs.
- Side effects: Side effects include drowsiness, constipation, dry mouth, tremors, muscle rigidity, and coordination problems. These side effects often make people stop taking the medications, which frequently results in a relapse of schizophrenia. A more serious side effect is tardive dyskinesia, a usually permanent neurological condition characterized by involuntary movements. To avoid tardive dyskinesia, the dosage of antipsychotics has to be carefully monitored. The atypical antipsychotics have fewer side effects than the older antipsychotic drugs and are less likely to cause tardive dyskinesia. In addition, relapse rates are lower if people continue to take the drug. However, the relapse rate is higher with these drugs if people discontinue the drug.
Criticisms of Drug Therapies
Drug therapies are effective for many people with psychological disorders, especially for those who suffer from severe disorders that cannot be treated in other ways. However, drug therapies have been criticized for several reasons:
- Their effects are superficial and last only as long as the drug is being administered.
- Side effects can often be more severe and troubling than the disorder for which the drug was given. This can cause patients to discontinue the drugs and experience relapses.
- Patients often respond well to new drugs when they are first released into the market because of the enthusiasm and high expectations surrounding the drug. But such placebo effects tend to wane over time.
- The therapeutic window for drugs, or the amount of the drug that is required for an effect without toxicity, varies according to factors such as gender, age, and ethnicity. This makes it difficult for physicians to determine the right dose of a drug.
- New drugs, even those approved for long-term use, are often tested on only a few hundred people for a few weeks or months. This means that the risks of taking drugs long-term are unknown.
- Some critics point out that because of pressure from managed care companies, physicians may overprescribe drugs rather than recommend psychotherapy.
- Drugs are tested only on certain populations, for certain conditions. Physicians, however, sometimes prescribe a drug for conditions and populations that were not included in the testing.
- Researchers who study the effectiveness of medications may be biased because they often have financial ties to pharmaceutical companies.
- Freely prescribing drugs for psychological disorders gives the impression that such disorders can be treated only biochemically. However, the biological abnormalities present in such disorders can often be treated by changing thoughts and behavior.
Electroconvulsive therapy (ECT) is used mainly for the treatment of severe depression. Electrodes are placed on the patient’s head, over the temporal lobes of the brain. Anesthetics and muscle relaxants help minimize discomfort to the patient. Then an electric current is delivered for about one second. The patient has a convulsive seizure and becomes unconscious, awakening after about an hour. The typical number of ECT sessions varies from six to twenty, and they are usually done while a patient is hospitalized.
ECT is a controversial procedure. Research suggests that there are short-term side effects of ECT, such as attention deficits and memory loss. Critics of ECT believe that it is often used inappropriately and that it can result in permanent cognitive problems. Proponents of ECT, however, believe that it does not cause long-term cognitive problems, loss of memory, or brain damage. They believe that it is highly effective and that it is underused because of negative public ideas surrounding it.
Psychosurgery is brain surgery to treat a psychological disorder. The best-known form of psychosurgery is the prefrontal lobotomy. A lobotomy is a surgical procedure that severs nerve tracts in the frontal lobe. Surgeons performed lobotomies in the 1940s and 1950s to treat highly emotional and violent behavior. The surgery often resulted in severe deficits, including apathy, lethargy, and social withdrawal.
Lobotomies are now rarely performed, but some neurosurgeons perform cingulotomies, which involve destruction of part of the frontal lobes. These surgeries are usually performed on patients who have severe depressive or anxiety disorders and who do not respond to other treatments. The effectiveness of these surgeries is unclear.
Transcranial Magnetic Stimulation
Transcranial magnetic stimulation (TMS) is a recently developed, noninvasive procedure. It involves stimulating the brain by means of a magnetic coil held to a person’s skull near the left prefrontal cortex. It is used to treat severe depression.