This book presents formulation development and evaluation of Diphenhydramine nasal nano-gel/emulgels,having lipophilic nano-sized interior droplets,with better penetration for targeted controlled delivery to mucous membrane. The combination of PG, PEG-1000 and Olive oil in nasal DPH nano-gel/emulgel can be utilized successfully for targeted controlled delivery. The optimized formulations have excellent permeability and prolonged residence time on mucosal surface, prove its good anti-histaminic activity in case of allergic rhinitis.