About This Skin & Immunity Support – Includes Colostrum and Astragalus Root which may support normal histamine levels and immune response. Antihistamine products help relieve itchy skin for dogs. Immune & Allergy Support – Senior Advanced Aller-Immune Bites are premium soft chews that support immune and digestive health along with antihistamine for dog allergies and itchy skin. Supports skin health for dogs. Contains EpiCor Pets – This advanced ingredient provides vitamins, protein, fiber, polyphenols, and antioxidants that are clinically proven to support natural immune defenses to keep your dog healthy and work against itchy skin allergies. Holistic Formula – These chewables also contain Colostrum, Quercetin, Vitamin C, and Yucca to support dog seasonal allergy relief, immune function, and digestive health. Prebiotic & Probiotic Blend – Each treat features five strains of Probiotics and PreforPro, a premium Prebiotic clinically proven to support healthy gut bacteria and the growth of Probiotic species. Delivered in allergy immune probiotic chews.