Dry Itchy Skin

[AimeeA]

I have a year old mix named Brady who has recently gone through some pretty stressful health issues these past three weeks and thankfully has recovered wonderfully. Although through the entire process we saw that he was trying to itch much more frequently, we originally thought it was just because he had to wear a protective cone and was trying to itch where his stitches were healing. Once we took the cone off he seemed to itch everywhere. We were told to give him Benadryl by a local vet to help suppress it but we don't know what it could come from. He sadly has not been on a constant food source for more than a few weeks so we don't know if that is a factor, or stress from his illness, dry skin, or a side effect from his medicine. We want to try bathing him with a good shampoo first but we don't know what kind would be best for the situation, suggestions would be greatly appreciated. Also he does seem to have dandruff from time to time. Oh he also doesn't have fleas we have given him flea medicine and check him daily for them.