The premise of biological forms of treatment is basically that pathologies, like any other illness, are caused by dysfunctions in normal chemical processes in the body. The goal of biomedical treatments is to alter the biology of the individual in order to return it to a normal level of functioning. The role of the therapist, like that of a physician, is simply to provide the appropriate form of medication. Two forms of biological treatments that are highly controversial are electro-convulsive therapy (ECT) and psychosurgery. ECT, which involves the deliberate induction of a seizure by passing electricity through the brain, is most effective not for the disorder it was created to treat, schizophrenia, but for severe cases of depression. Psychosurgery, which involves the surgical destruction of specific portions of the brain, has evolved from such procedures as pre-frontal lobotomies to pinpointing small, precise portions of the brain, as in cingulotomy.

Psychopharmacology, or the study of the use of medications to treat psychological disturbances, is probably the most promising form of biological treatments. Psychoactive drugs, or chemical substances that alter psychological states, can be divided into eight basic categories: anti- psychotics, antidepressants, psychomotor stimulants, antimanic, anxiolytic, sedative hypnotic, antipanic, and anti-obsessional. Some drugs, such as fluoxetine (Prozac), fit into more than one category, and certain disorders, such as panic disorder, require the use of drugs from different categories. Like any medication, these drugs also have side effects, some of which are so unpleasant that they lead to the discontinuation of use by the individual and subsequent relapse. It is impportant to mention that, since psychopharmacology offers symptom relief and not cures of the underlying causes of a disorder, the length of treatment is usually long-term.