This quantitative and qualitative study examines the chronological development of the possessive determiners mine, my, thine, and thy in the Early Modern English Medical Texts corpus (EMEMT), focusing on the influence of phonological environment and text category, as well as noting lexical items with which mine and thine commonly occur. The pattern of decline for mine and thine, the phonological context in which they are found, and the collocations identified resemble those found in previous research, but rather than occurring in more formal texts as suggested by previous research, these forms predominantly occur in the more “popular” medical text categories, those with a wider readership, and particularly in texts that are more speech-like in nature (cf. Kytö and Walker 2020).