Hair loss is a side effect from Mesalamine
, which is an NSAID (non-steroid anti inflammatory). Treatment with NSAID's creates a shock to your system which transforms hairs in the growing stage to the dormant stage (for a few months) and then the shedding stage. This is why you don't see the shedding until a few months in. The damage is done when the hair is rendered dormant, but the shedding that follows takes a few months. Do some research on NSAID's and hair loss.