Abstract
BACKGROUND: Nasal drug delivery offers a non-invasive route with rapid absorption and the ability to bypass first-pass metabolism, making it promising for central nervous system (CNS) disorders, nasal diseases such as allergic rhinitis, and other chronic conditions by enabling targeted delivery and crossing the blood-brain barrier. PURPOSE: To review the advantages of nasal delivery, therapeutic potential of natural products, and how drug delivery systems may overcome bioavailability and solubility issues. STUDY DESIGN: A literature review analyzing mechanisms, clinical applications, and limitations of natural products in nasal delivery. METHODS: Relevant articles published before January 2025 were retrieved from Google Scholar, PubMed, ScienceDirect, Scopus, Web of Science, Springer, and official sources. RESULTS: Nasal administration improves the bioavailability and absorption of natural products, enhancing anti-inflammatory, antioxidant, neuroprotective, and anti-allergic effects. However, poor solubility and stability remain barriers, which may be mitigated by nanocarriers, liposomes, and other advanced systems. CONCLUSION: Combining nasal drug delivery with natural products is a promising strategy for treating CNS, nasal, and chronic diseases, potentially improving clinical efficacy and expanding therapeutic options.