Milk of Magnesia. A small dose of Milk of Magnesia milk might do the trick for Fido. Ask your vet, however, before administering anything to your dog.
Supplements are available for canines with a constipation problem. You can find companies like "The Natural Canine" that specialize in holistic solutions to constipation and other ailments that dogs can experience. These supplements have additives such as acidophilus, folic acid. , and vegetable enzymes, all which can be cures to canine constipation. Again, seek a vet's guidance before you change the diet of your
