The spelling of the word "pathoamine" can be explained using IPA phonetic transcription. "Patho" is pronounced as /ˈpæθoʊ/, which represents the syllables "pa" (with a short "a" sound) and "tho" (with a long "o" sound). "Amine" is pronounced as /əˈmin/, which represents the syllables "a" (with a neutral vowel sound), "mi" (with a long "i" sound) and "ne" (with a silent "e"). Therefore, the correct spelling of this word is "pathoamine".
A ptomaine.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.