Rash on my Shitzu

Question
I have a 12 year old male Shiatsu who is neutered.  In the past 2 years he has developed a rash of sorts in his arm pits and under belly (mostly back half).  He seems to get it mostly in the wrinkled parts of his body where he seems to have an excess of skin.  It really starts to stink and he is always trying to bite at his legs to stop the itching.  I use a shampoo from the vet which has oatmeal in it.  I have him on hypoallergenic dog food from the vet and he does not get any other food unless he gets lucky enough to find a scrap or two around left by my children.  What could this be and is there anything I can do to help him feel better?


Answer
Sounds like allergies, You can keep doing what your doing with the hypo alergtic kibble and the shampoo(don't bath often it causes Dry'er skin) and give him One Benadryl Pink oblong shaped 25 ML caplet every 24 hours if there is little inprovment you can do One every 12 hours...I use these with my two small terrier as they have allergies it relives alot of the itching and hot spots as well....my vet reccomended these pills to my dogs on several occassions of allergy breakouts....and in the begining they did cause some sleepiness but that has subsided now.