My horse has bad sunburn, what should i use?

hi, my horse lives out of a day and night during these warmer months. he is a piebald and has a pink nose. lately he has been coming in with very bad sunburn. its very red and flakes very easily and looks very sore. can anyone recommend any lotions/potions to use. any particular sun cream? and can you buy a specific mask type thing which just protects that area of his face? thanks in advance for anything anyone can tell me.