Every year, one million people die from neurological disorders such as Alzheimer’s disease, Parkinson's disease, and glioblastoma multiforme. Nanotechnology has the potential to revolutionize the treatment of neurodegenerative diseases by stimulating physiological responses. It reduces adverse effects by provoking, reacting to, and interacting with target sites that use engineered materials and devices that interact with biological systems at the molecular level. The blood–brain barrier (BBB) is a key barrier that inhibits therapeutic drugs from reaching their intended targets. This highlights the importance of using nanotechnology to manipulate biological processes in order to accomplish desired results. Nanoparticles, due to their nanoscale size, are a strong alternative for medication delivery that can penetrate the BBB. These mechanisms not only improve drug stability but also make medication passage through the BBB easier. By providing a more effective technique to dispense drugs, nanotechnology has the potential to improve neurological disease therapy and diagnosis procedures. Drugs can be designed using nanotechnology to perform a range of roles, including traversing the BBB, focusing on specific cells, and stimulating nerve cell renewal and maintenance.