Glandex is safe for both dogs and cats because it is designed and approved by veterinarians using only natural components. It's a good option for pets with chronic anal gland issues. Yet because of the higher fiber content of Glandex, some dogs may initially have constipation or moderate side effects like diarrhea, soft stools, or upset stomach. Before administering any vitamins to your pet, it is always advised to seek advice from a veterinarian.