The flux of pharmaceutical industries has altered a lot over the last 30 years. Innovation is extremely necessary for such industries and this innovation comes from research & development. Operations Research is needed as drugmakers around the world want to manage cost, quality and speed. Maximising the efficiency of production, labour and equipment is an important way for top-quartile drug makers to break out of the pack. The purpose of this research paper is to highlight OR approaches used in the pharmaceutical industry, that are backed by statistics, and observe the changes related to this industry, over the years. We went through qualitative research papers and gathered various mathematical models that link Operations Research with the current happenings of the Pharmaceutical Industry. The paper illustrates the main issues related to optimization in the industry and how science and technology help to overcome them by making the right forecasts and decisions.