I have kidney issues (stage 4) and I am allowed 250 mg azithromycin every other day indefinitely and have been on this for at least 5 months so far with no change in kidney function. (This is a treatment for pseudomonas which is not agreed to by many members of this forum because of the possibility of resistance and other reasons. ) My kidney doctor is very very careful and has not suggested that this is a problem but the dosage is reduced in half from 500 to 250. This is all I can say. It could all be wrong and I am sure there is disagreement but I have to follow some doctor's advice and so far I am doing well.