My shins and lower legs are red in colour. I am getting blisters on my shins. They clear up then they appear again. They range from small circular blisters quarter of an inch in diameter or less to oval shaped blisters that can be up to one inch long. I suffer from type2 diabetes but my blood sugar levels are very good with the medication I take. 1000mg metformin, 2.5mg linagliptin (twice a day) and 40mg Gliclazide (once a day). These blisters which turn into scabs make my legs look unsightly and as I love swimming I find their appearance disturbing. What could be the cause of these recurring blisters?