The allergies that your pug is suffering from have caused its skin to itch and thicken.  The best way to treat this allergic reaction to something in its environment, is to have the vet give you prescriptions for antibiotics, and a shampoo that will help your dog’s skin feel better.  The next thing that you have to do is to find out what in your home, is causing the pug to have allergies.  Think of what has been added to the home, that was not there previously, and you will find the problem.  It could be a new carpet, houseplant, air freshener, or even a new blanket or pillow, could have properties that are causing the problem.  It will take some investigating, but you will find the allergens, and remove them, so that the pug can regain its peaceful, happy life.