Many types of research are going on for the development of novel drugs to treat neurodegenerative diseases like epilepsy, Parkinson’s disease, Alzheimer’s disease, but the major problem during the drug development is that the pharmacotherapy of such drugs is restricted by the actions of drug transporters in the blood-brain barrier. P glycoprotein is also one of the drug transporters in the blood-brain barrier which is there to restrict the entry of many substances like xenobiotics, toxicants into the brain cells. It also effluxes drug content from the cells which is the main reason for the reduced pharmacotherapy. To obtain the maximum therapeutic effect drug have to enter into the cell which is difficult when p glycoprotein is in action that’s why we have to modulate or inhibit the p glycoprotein action in the blood-brain barrier.