Pedigree is like feeding a dog Twinkies or French fries as their regular diet.
If your current kibble is making your dog sick, you may want to feed a different protein source, such as fish or lamb (Nature's Recipe is chicken based, I think?), or go to a grain free kibble (some dogs are sensitive to grains). Acana is a good food, and it comes in several varieties. Blue Buffalo is also a good food. Both come in both grain and grain free varieties. These foods may be more expensive, but you will feed less of it, because they're more nutrient dense. In fact, if you overfeed, it can cause diahrrea. You can also add a spoonful of plain pumpkin (NOT pumpkin pie filling) to the food. The fiber helps firm things up.
If you can't afford these brands, you might try Pro Plan Sensitive Skin and Stomach. Some people have had good luck with this food. You can get it at Petsmart or Petco.