Abstract: The blood-brain barrier (BBB) is a selectively permeable physiological barrier that regulates the passage of substances into the central nervous system (CNS). Even though they are critical in maintaining brain homeostasis, the BBB severely restricts drug delivery, one of the most serious obstacles in the treatment of neurodegenerative disorders such as Alzheimer's disease (AD). Small-molecule drugs, biologics, and gene therapies are impermeable across the BBB due to their restrictive properties, including tight junctions, efflux pumps, and metabolic enzymes. In an attempt to bypass this barrier, novel drug delivery systems have been designed. These are nanoparticle-based carriers, receptor-mediated transcytosis, targeted ultrasound with microbubbles, and lipid-based drugs. Exosome-based nanomedicine is highly promising since it naturally penetrates the BBB and can transport therapeutic drugs, including neuroprotective molecules, monoclonal antibodies, and RNA-based therapies. Engineered exosomes are a highly promising platform for targeted drug delivery with low systemic toxicity and high drug bioavailability. Even with promising advancements, there are still some challenges, such as bulk-scale production, purification, cargo loading efficiency, and targeting specificity. Future studies should focus on optimizing exosome engineering, enhancing delivery platforms, and conducting large-scale clinical trials to assess safety and efficacy. Through the development of such new drug delivery systems, scientists can uncover novel therapeutic potential for Alzheimer's disease and other CNS disorders, ultimately leading to improved patient outcomes.