How much more years do you have to study when a pharmacist degree and want become doctor?

The path from a pharmacist degree to becoming a doctor requires completing medical school. This typically takes four years after completing all prerequisites. These prerequisites can vary but generally include a significant number of science courses which may or may not be covered by a pharmacy degree. Some schools might accept some of a pharmacist's coursework to shorten the process slightly, but this is not guaranteed. Therefore, it's safe to estimate an additional four years, plus possibly some time spent completing additional pre-med prerequisites.