hydantoin

n. any of a group of drugs developed primarily to control epileptic seizures. They were introduced in 1938 after careful studies of chemicals capable of suppressing electroshock convulsions without also causing adverse effects on the central nervous system. Hydantoin molecules are similar in structure to barbiturates but have the advantage of not altering the threshold for minimal seizures. The prototype of the hydantoins is phenytoin (previously called diphenylhydantoin). Other hydantoins include mephenytoin (U.S. trade name: Mesantoin) and ethotoin (U.S. trade name: Peganone), but these are rarely used.

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Psychology term of the day

May 8th 2024

Down syndrome

a chromosomal disorder characterized by an extra chromosome 21 and manifested by a round flat face and eyes that seem to slant (the disorder was formerly known as mongolism). Brain size and weight are below average; affected individuals usually have mild to severe intellectual disability and have been characterized as having docile, agreeable dispositions. Muscular movements tend to be slow, clumsy, and uncoordinated. In many cases, growth is stunted, the tongue is thick, and the fingers are stubby. Affected individuals may have heart defects and respiratory insufficiencies or anomalies that are often corrected during infancy by surgery. However, lifespan is reduced compared with that in the general population, and affected individuals typically show early onset of Alzheimer’s disease. Down syndrome is one of the most common physiological causes of intellectual disability. Also called Langdon Down’s disease; trisomy 21. See also autosomal trisomy of group G. [described in 1866 by John Langdon Haydon Down (1828–1896), British physician]