Forerunners of chlorpromazine were promazine and diethazine (A.E. Caldwell, 1970).
Chlorpromazine was first synthesized in the laboratory in 1950. Though many drugs like LSD and aspartame are chance discoveries, chlorpromazine may be regarded as a product of successful drug engineering.
Subsequently chlorpromazine gained a reputation as an antipsychotic drug. The clinical reports agree in large measure that chlorpromazine appears to be useful in the management of agitation and manic states in psychoneurotic patients. Clinical reports from 1955 revealed the novelty and effectiveness of chlorpromazine at that time. Bleuler and Stoll wrote,
"... reserpine and chlorpromazine soothe and relax patients to an extent formerly unknown to the doctors writing this report ... after 2-3 days of excessive sleeping, from which the patient can be awakened, the patient's mood is more indifferent, less impulsive, quieter, and more relaxed." (M. Bleuler, 1955)
Chlorpromazine has been beneficial in a variety of conditions presenting a picture of psychomotor excitement. At the time, it was considered to be an advance over sedating drugs or physical restraints, but chlorpromazine is not in use anymore. It has been replaced by newer drugs haloperidol and risperidone.
At the time when chlorpromazine became popular, physicians said that the sedative effect of chlorpromazine is not associated with clouding of consciousness, impairment of judgment or disinhibition of affect; that chlorpromazine can reduce severe anxiety, diminish phobias and obsessions, reverse or modify a paranoid psychosis, quiet manic or extremely agitated patients, and change the hostile, agitated, demented patient into a quiet, easily managed patient. But its not in use anymore, calling into question the effectiveness of the drug.
According to Caldwell, chlorpromazine is one of the most important drugs in the treatment of wild animals and in their relocation to preserve wildlife.
In 1954, it was thought that chlorpromazine might block the effects of LSD or mescaline. However, some humans reported an unpleasant intensification of LSD effects when combined with chlorpromazine or reserpine. Ketanserin, which binds 5-HT2A receptors, appears to be a more specific drug for antagonizing LSD and mescaline intoxication than chlorpromazine.
The average daily dose of chlorpromazine is 300-500 mg by mouth, which is equivalent to a dose of 75-150 mg intramuscular. If chlorpromazine is given intravenously it must be diluted with glucose to avoid irritation with the venous walls.
Caldwell A. E. Origins of psychopharmacology, from chlorpromazine to LSD. Charles C. Thomas: Springfield, 1970.
original publish date: March 14, 2012