Many people have allergies related to
penicillin and it's derivatives like amoxacillin. Usually doctors prescribe an sulpha or a cephalosporin antibiotic in these cases, such as k-flex/cephalexin among others.
Since you are prone to urinary tract infections (U.T.I) and kidney infections you should maybe ask your doctor about an antibiotic called "Ertapenem". It can be used for uti's and other infections from gram (-) bacteria. There is another one that usually kills the same type of bacteria as Ertapenem called "Cefoxitin" (I think thats how to spell it). Maybe even "Imipenem" could help.
I would ask your doc about those 2 antibiotics. There are alot of doctors that do not know every antibiotic by it's name so they might need to check on thier computer first.
Hope this helped.