The present invention provides a water continuous dispersion of nanoparticles. The water continuous dispersion includes: one or more aromatic amide anesthetic compounds; one or more polyethoxylated high HLB surfactants; one or more low HLB surfactants; one or more oils, wherein one or more nanoparticles of a dispersed phase include a lipid bilayer, and wherein ratio of oil to surfactant is between about 0.12:1 to about 3.5:1. Methods of preparing various water continuous dispersion of nanoparticles are also provided.