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phe·nyt·o·in | \ fə-ˈni-tə-wən 
\
\Definition of phenytoin
: a crystalline anticonvulsant compound C15H12N2O2 used in the form of its sodium salt in the treatment of epilepsy
— called also diphenylhydantoin
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phenytoin
nounphe·nyt·o·in | \ fə-ˈnit-ə-wən \
\Medical Definition of phenytoin
: an anticonvulsant used often in the form of its sodium salt C15H11N2NaO2 to prevent or treat seizures
— called also diphenylhydantoin
— see dilantinComments on phenytoin
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The first known use of phenytoin was in 1941
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