I'm not terribly clued up on what meds are used to treat fistulas; the biologics, obviously (Remicade and Humira; note: Remicade is the brand name for Infliximab). Antibiotics are sometimes used, but I think that's more to prevent/treat possible infections - not sure. Also, I'm not sure if the thiopurines (6MP and azathioprine) have any role to play in healing up fistulas. They take so long to work, perhaps not.
Personally, I'd be fighting to get onto Remicade. It's licenced to treat fistulizing disease in the UK. See 1.3:
www.nice.org.uk/guidance/TA187/chapter/1-guidanceCheck this link out too, topic creator. It's the NHS's 'map of medicine' for treating fistulising Crohn's disease. Click the i's in each box for more info.
healthguides.mapofmedicine.com/choices/map/crohn_s_disease3.htmlI've never heard of being refused Crohn's meds due to a fistula. Most of the Crohn's meds are used to treat fistulas! The only class of meds which will definitely be a total waste of time are the 5-ASAs (Pentasa, Asacol, etc.). There are the mildest and are antinflammatories. They don't even help regular Crohn's disease, let alone fistulizing Crohn's disease. (Probably 'cos 5-ASAs only treat the surface mucosa and Crohn's goes well beyond that.)