Immunitone Plus™ is an herbal formula that is designed to support healthy immune system function during cold and flu season. It contains herbs that support normal natural killer (NK) cell activity and the balance of cytokines, which are the regulatory proteins released by immune cells as part of a normal immune system response.* The standardized herbs in this formula contain optimal and consistent amounts of the most active ingredients. Immunitone Plus™ is suitable for long term use and for all age groups.