Wiktionary
metisazone
n. (alternative form of methisazone English)
Wikipedia
Metisazone
Methisazone ( USAN) or metisazone ( INN) is an antiviral drug that works by inhibiting mRNA and protein synthesis, especially in pox viruses. It has been used in the past to treat smallpox.
Methisazone has been described as being used in prophylaxis since at least 1965.