Teaching an ESP course is significantly challenging due to its practical, contextual, and communicative nature as a “language in context” and a prerequisite for acquiring professional skills and job-related functions that require real life learning situations to imitate specific professional settings and accentuates practicing the essential English language skills that students would primarily employ in their future fields. This paper presents an andragogy-based customized blended learning model for English in Medicine course introduced to students of the preparatory year program during COVID-19 pandemic. Integrating andragogical principles, the course identifies students’ access to multimodal tools for required English Language skills and medical vocabulary, including a virtual listening lab for augmenting listening skills, a virtual medical library for boosting online medical reading, a virtual hospital of different doctor-patient interaction scenarios for practicing the use of language in context, course community blogs and audio discussion forums for enhancing writing and speaking skills, an online medical dictionary for understanding and translating medical terminologies and integrated Kahoot games for testing field related knowledge. A mixed methodology of pre-test and post-test research design along with a learning satisfaction survey were used to evaluate the change in variables which were students’ English Language proficiency, cognitive competence, learning motivation, and learning styles. The study findings establish the effectivity of the shift from pedagogic to andragogic strategies in the course. It supports integrating pedagogic constructive theories along with adult learning theories and blended education theories to ensure productive teaching and learning of ESP courses in accordance with the constrictions of quality modern education.