I have heard that doxycycline brings down the inflammation and sticking of the cartilage. That rings true with the news of another member who said that his AS went away whilst he was taking doxy for malaria when he was staying in Singapore, but the AS returned afterwards. There is another record of it reducing the spine-sticking in someone else. [sorry I do not have a ref. just now]
Doxy has been suggested in another place as a helpful therapy for cartilage [heart] for its anti- ? and ? properties. [darn that memory!!] Theres going to be a trial I think. ...perhaps someone else can fill in here....
I have never taken meds. for AS - the diet has been sufficient. My spine stuck for a short time in a couple of places but I was able to free it up.
The diet does not cause extreme weight-loss as there are plenty of other carbohydrates available. I think the difficulties only relate to ones lifestyle - if you are used to eating highly manufactured foods instead of basic vegetables, fruits or proteins separately, then it is hard [if not impossible] to separate out the starch.
Factories even add starch to bacon theses days!!!!!!

PreAS = STARCHfree, yoghurt, ,, meat , vitE, niacinamide,B complex
Fibro = antiviral, MAGNESIUM /B6
Arthritis in fingers = no potato fam. plants
Candour & laws differ from place to place