Social media has moved ahead of just being a tool for adolescent users to share their personal lives (messages, pictures) but has also been taken up by healthcare stakeholders to disseminate health information worldwide. The role of social media in healthcare industry and impact of patient engagement has moved to centered-stage and is continuously propelled by patient demand, mobile technology and mounting influence of the native digital generation. The pace with which the social activity is growing, it is important to foresee what impact these web-based platforms are having on the deliverance and outcome of healthcare interventions. This survey looks at how far social media has been prove to be effective in disseminating health information and to what extent ontological advancing approaches have been helpful in extracting relevant knowledge from sheer amount of healthcare data.