The present invention relates to a nanoparticulate topical composition comprising (i) nanoparticles of a water soluble and water susceptible active ingredient or its pharmaceutically acceptable salt, having a particle size distribution such that 90% of the particles are less than 1000 nm, (ii) one or more wetting agent and (iii) a non-aqueous liquid vehicle, wherein the composition is free of water. The present invention also relates to a method of treating acne, rosacea, impetigo or a skin disease caused by a bacteria, by topical application of a nanoparticulate topical composition comprising nanoparticles of a water soluble and water susceptible active ingredient or its pharmaceutically acceptable salt, having a particle size distribution such that 90% of the particles are less than 1000 nm.
