System Strength Formulated with Vitamin C, Echinacea, and Elderberry Dietary Supplement Our Immune Support capsules provide more than twice your daily vitamin C along with these well-known immune health botanicals: Echinacea – Supports a healthy immune response, especially at the start of an immune system challenge. Elderberry – Promotes a balanced overall immune response, possibly through affecting macrophage activity. This nutrient-herbal blend provides focused immune support, especially at the onset of an immune system challenge.