Spots found under the tongue

My male husky had a serious allergic reaction a year and a half ago to straw that I had put in his kennel.  I later found out that it was barley straw.  I've recently noticed that he had greenish spots underneath both sides of his tongue.  The spots are round circles, they do not look like blisters.  The areas that are discolored are flat and stick out a bit more than the regular thickness of the tongue but seem rigid.  I brought him to a vet's but they could not get a proper look at him without first putting him to sleep.  What they were recommending, I could not afford to do so they gave him antibiotics.  He is nearly done the medications and there does not seem to be any improvement.  I have also changed his food as I thought it could possibly be an allergic reaction to some grain in the food and he is now on an all natural food that contains no corn and is higher in protein.  To see him, he does not look ill at all.  He is still very energetic is eating well and drinking.  Any idea what it could be or what else I could try?

[Cliff Redford, DVM]

this does not sound like an allergic reaction but instead sounds like a case of papillomatosis. The papilloma virus cause different lesions in the mouth, often like what you are describing. An internet search will bring up images for you to see and if it is similar then just be patient, the virus will run its course and eventually the lesions will disappear.