The Weil Immune Support Formula is an exclusive combination featuring Astragalus, a tonifying herbal remedy prized in traditional Chinese medicine. This evidence-based vegetable capsule formula also contains a potent blend of immune supportive polypore mushrooms, including Maitake and Reishi. Taken on a regular basis, the unique combination of ingredients found in the Weil Immune Support Formula may support a healthy immune system. Andrew Weil, M.D., donates all his after-tax profits from the sale of Weil Nutritional Supplements to the Weil Foundation, an organization dedicated to sustaining the vision of integrative medicine.