I went to the beach on Friday and was careful to wear sunscreen. However, I burned my scalp really badly. The next day (Saturday) my scalp was really tender and red. Today, I noticed some pus-filled blister on my scalp. Now, I have hundreds of them! They are VERY painful, and full of white pus. I have a friend who's a nurse. She said it sounds like sun poisoning, and that I need a Prednisone (oral) prescription.