I have a 24 week old TT who has been nibbling his legs ( front and back), and a patch on his back shoulder. Resulting in hair loss. He is currently being treated with Frontline and Spot On for flea and mite infestation.....none of which are obvious. His diet has been changed from RoyalCanine to Burns in case this disorder is food related. He has not lost his appetite !!!

Has anyone had an experience like this? Any advice ?