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fosphenytoin

American  
[fos-fen-i-toh-in, -fuh-nit-oh-in] / ˌfɒs fɛn ɪˈtoʊ ɪn, -fəˈnɪt oʊ ɪn /

noun

Pharmacology.
  1. a prodrug that produces phenytoin and is taken to prevent or treat seizures.