Described herein are methods for treating interstitial cystitis in a subject comprising administering to the subject an effective amount of a compound which is a modified hyaluronan or a pharmaceutically acceptable salt or ester thereof, wherein said hyaluronan or its pharmaceutically acceptable salt or ester comprises at least one sulfate group and the primary C-6 hydroxyl proton of at least one N-acetyl-glucosamine residue is substituted with an unsubstituted alkyl group or fluoroalkyl group.
