Due to rise in the LLM’s, there is a huge revolution experienced in different domains like education, marketing, medicine development, healthcare and finance. The aim of the paper is to identify and explore all the applications, pros and cons in healthcare, specifically the focus is given to detection of different disease. Major LLM’s which can be used for the disease detection are GPT 4, LLaMA, ChatGPT and GPT 3.5. Out of all these, GPT 4 is the most widely used for disease detection and healthcare due to accuracy and efficiency. The experiments are carried out using different medical data sources like medical images, documents related to disease, general database and genomic data. There are wide results possible using this LLM’s like chronic issues, cancer diagnostics, respiratory disease and many other rare diseases. The evaluation of the models in identification of these disease is done in both qualitative and quantitative manner. The findings show the evolution of the LLM’s in the field of medical science and the future of it in improving the disease detection.