psychopharmacology (sī'kōfär'məkŏl`əjē), in its broadest sense, the study of all pharmacological agents that affect mental and emotional functions. The term is usually applied more specifically to the study and synthesis of drugs used in the control of psychiatric illnesses, namely the antipsychotic, antianxiety, antidepressant, and antimanic medications. The widespread use of drugs among individuals suffering from mental illness is a relatively recent phenomenon, developing since the 1950s.

Antipsychotic Drugs

Antipsychotic drugs can ameliorate the types of delusions delusion, false belief based upon a misinterpretation of reality. It is not, like a hallucination, a false sensory perception, or like an illusion, a distorted perception.
..... Click the link for more information. and hallucinations hallucination, false perception characterized by a distortion of real sensory stimuli. Common types of hallucination are auditory, i.e., hearing voices or noises and visual, i.e., seeing people that are not actually present.
..... Click the link for more information. characteristic of bipolar disorder (see depression depression, in psychiatry, a symptom of mood disorder characterized by intense feelings of loss, sadness, hopelessness, failure, and rejection. The two major types of mood disorder are unipolar disorder, also called major depression, and bipolar disorder, whose
..... Click the link for more information. ) and schizophrenia schizophrenia (skĭt'səfrē`nēə)
..... Click the link for more information. . The first drug of this type was reserpine reserpine (rĕsûr`pēn), alkaloid isolated from the root of the snakeroot plant (Rauwolfia serpentina
..... Click the link for more information. , whose use dates from ancient Hindu medicine but whose reintroduction as an antipsychotic agent in 1954 marked the beginning of the large-scale use of antipsychotic drugs. Because of side effects, including depression, reserpine has been supplanted by phenothiazine phenothiazine (fē'nəthī`əzĭn), any one of a class of drugs used to control mental disorders.
..... Click the link for more information. drugs. The phenothiazine chlorpromazine chlorpromazine (klōrpräm`əzēn')
..... Click the link for more information. (Thorazine) was the first to be widely applied to mental disorders and remains one of the standard drugs. Drugs of the phenothiazine family are most useful in the treatment of schizophrenia. They are thought to act in part by blocking dopamine receptors at the synapse, reducing brain activity. The phenothiazines and clozapine have been credited with a revolutionary transformation of mental health care, enabling increasing numbers of psychotic persons to function outside the hospital. Antipsychotic drugs may have negative side effects, such as the dulling of physical and mental functioning, tardive dyskinesia, and sedation.

Antianxiety Drugs

Antianxiety drugs antianxiety drug, drug administered for the relief of anxiety . Although their action is not fully understood, most antianxiety medications appear to affect the action of neurotransmitters in the brain (see serotonin and norepinephrine ).
..... Click the link for more information. , including the propanediol meprobamate meprobamate (məprō`bəmāt')
..... Click the link for more information. (Miltown or Equanil), and the more recent benzodiazephines—such as diazepam (Valium)—have found wide use in reducing tension and anxiety among individuals with less serious mental disorders, but may lead to addiction if abused. Although they form a chemically diverse group, the physiological effects of each are similar; in small doses they relieve anxiety by reducing muscular tension, and in larger doses they produce sedation, sleep, and anesthesia (see depressant depressant, any one of various substances that diminish functional activity, usually by depressing the nervous system . Barbiturates , sedatives , alcohol, and meprobamate are all depressants. Depressants have various modes of action and effects.
..... Click the link for more information. ). Antianxiety drugs are the most frequently prescribed pharmaceuticals in the United States.

Antidepressants

Antidepressants appeared in the late 1950s, and have been used in the treatment of individuals suffering from major depression or the depression phase of bipolar disorder. Antidepressants include the tricyclics and monoamine oxidase (MAO) inhibitors. These drugs have the effect of increasing the concentration in the nervous system of catecholamines catecholamine (kăt'əkôl`əmēn)
..... Click the link for more information. such as epinephrine epinephrine (ĕp'ənĕf`rīn), hormone important to the body's metabolism, also known as adrenaline.
..... Click the link for more information. . The toxic effects of the MAO inhibitors have been largely overcome in recent years, and the drugs are still used in many instances. They have been supplanted in many uses, however, by tricyclic compounds, such as amitriptyline (Elavil), and the newer serotonin serotonin (sĕr'ətō`nĭn), organic compound that was first recognized as a powerful vasoconstrictor occurring in blood serum.
..... Click the link for more information. increasers, such as fluoxetine (Prozac) and sertraline HCL (Zoloft). Tricyclics are chemically similar to phenothiazines, but that activate rather than tranquilize (see stimulant stimulant, any substance that causes an increase in activity in various parts of the nervous system or directly increases muscle activity. Cerebral, or psychic, stimulants act on the central nervous system and provide a temporary sense of alertness and well-being as
..... Click the link for more information. ). The choice of an antidepressant antidepressant, any of a wide range of drugs used to treat psychic depression . They are given to elevate mood, counter suicidal thoughts, and increase the effectiveness of psychotherapy .
..... Click the link for more information. often has more to do with its side effects than efficacy.

Antimanic and Hallucinogenic Drugs

The element lithium lithium (lĭth`ēəm) [Gr.,=stone], metallic chemical element; symbol Li; at. no. 3; at. wt. 6.941; m.p. about 180.54°C;; b.p.
..... Click the link for more information. , in the form lithium carbonate, has been widely used as an antimanic in cases of bipolar disorder (manic-depression), particularly to control manic episodes. Lithium alters the transport of sodium ions in nerve and muscle cells and affects the metabolism of catecholamines; the exact mechanism of action is unknown. The hallucinogenic drugs, such as mescaline and LSD LSD or lysergic acid diethylamide
..... Click the link for more information. , have been of research interest because they often mimic natural psychotic states.

psychopharmacology

Study of the effect of drugs on the mind and behaviour, particularly in the context of developing treatments for mental disorders. Major psychopharmacological advances in the 20th century include the development of tranquilizers, antidepressants, lithium carbonate (for bipolar disorder), certain stimulants (including amphetamines), and antipsychotic agents such as chlorpromazine (Thorazine), fluphenazine (Prolixin), and haloperidol (Haldol).