Diagnosing parkinsonism at an early stage can be very difficult. For many people with Parkinson's disease, it takes a long time (sometimes years) before the final diagnosis is made. The symptoms in the early years are often not specific only to Parkinon’s diseases, but can be applied to other diseases are well. The diagnosis is made an experienced neurologist based on examinations and the patients’ observations. The diagnosis is further supported by monitoring the evolution of the disease as well as the response to medicine.