I know from a human point of view – if the skin is itchy especially from a yeast infection – eating probiotic yogurt is good but possibly consider putting it on his skin as it is really cooling and soothing from the fridge. Also acidophillus (the good bacteria) are available in capsule form so you may be able to give him some of them. Rather than give him capsules you can open them on sprinkling them on/through his food. These are good from a human point of view so i would check them out (with a vet etc) before administering them to him. Anything that may help this lovely boy. Can’t wait to see photos as he is improving.