Bamboo Pharmacy Winter Defense is a blend of Honeysuckle, Chrysanthemum and ancient Chinese herbs used for short-term support of a healthy respiratory system and a healthy immune system response. This product is based on the Chinese formula Gan Mao Ling, known for decades for supporting the body's healthy immune response when defenses are down. The herb Evodia Lepta has been compared to Echinacea for its immune system enhancing qualities while simultaneously releasing the exterior. May be proactively used when in over-exposed environments. Appropriate for short term use.