Herbal drug delivery for ocular treatments-an updated review

The aim of this review is to address the challenges faced by traditional dosage forms in ocular herbal drug delivery and to demonstrate the potential offered by nanotechnology to overcome related challenges. This study employed a systematic investigation approach, focusing on nanocarrier systems and advanced material-based strategies documented in the literature. Various nanoformulation systems, including in situ gels, liposomes, ethosomes, transfersomes, exosomes, polymeric and lipid-based nanoparticles, emulsions, nanofibers, and dendrimers, are extensively evaluated. The contribution of innovative nanomaterials, such as nanozymes and metallic and ceramic nanoparticles, to herbal drug delivery is assessed. Different herbal secondary metabolites with potential indications for ocular diseases are reviewed. The reported findings in the literature demonstrate that nanotechnology can enhance the solubility and stability of plant-derived active ingredients, enabling controlled release in target tissues and thus enhancing therapeutic efficacy. Furthermore, safety, toxicity, and regulatory frameworks are scrutinized. In summary, this review highlights the opportunities offered by nanotechnology-based systems in herbal medicine applications and guides integrating of alternative herbal therapies with allopathic approaches in the future.