Has he been to the vet for his excessive paw licking? Does his paws smell like fritos @ all? It could be yeasty bacteria, it's incredibly itchy. A simple skin scrape w/cytology will tell the vet what it is.
Depending on what the diagnosis is, if it is yeast, you must eliminate all sugary foods. No potatoes, no tapioca, no grains, no treats containing molasses, brown sugar, honey, etc.
Eating These Foods Can Cause Dog Yeast Infection