A hydrogel composition for treatment of interstitial cystitis is described and comprises crosslinked hyaluronan particles dispersed throughout a crosslinked hyaluronan hydrogel matrix, wherein the hyaluronan is high molecular weight hyaluronan. The composition is formulated for direct bladder instillation in a human. The hyaluronan particles are nano-sized hyaluronan particles, or agglomerates of nano-sized hyaluronan particles, or a mixture thereof.