I can eat any other onions on the market. Only the Vidalia species causes this reaction and it only takes a very small amount. I have to be so very careful during the summer when the vidalias are in the stores. I recently ate a small amount of potato salad that contained only 1/3rd of a vidalia onion in 10 pounds of salad and ended up in the ER. What can possibly be in the vidalia that causes this reaction when other onions are perfectly fine?