You can pursue machine learning specialization in healthcare and drug discovery. As you are a doctor, you know the domain knowledge of healthcare.You can do wonderful application development in healthcare through AI. You should start with basic algorithms of machine learning, first. After a few algorithms learnt, you can jump on to image analysis through deep learning framework like CNN. Image analysis automates the diagnosis from various types of medical images like x ray, ct scan, retinopathy images etc. There are many more elements to discuss. I am writing a ebook on machine learning for healthcare. Hope it would help people like you.I can't recommend any courses as I haven't evaluated any.
Arun Kumar Sharma, Chief Consultant Analytics and Equity Research (2012-present)
Source: Quora Digest