Hay fever is when the body’s immune system reacts excessively to substances that are harmless in themselves, like plant pollen such as from certain grass and tree pollen. Typical symptoms are reddened, itchy eyes and a blocked, runny and itchy nose.
In Chinese Medicine, hay fever is caused by Wei Qi Deficiency, Disharmony of Ying and Wei and External Wind Invasion. External Wind may be invading together with Cold or with Heat, Cold is tied to the superficial skin, Heat disturb superficial skin, and Yang Qi can’t sparse, so there is sneezing when sprayed up, Cold or Heat disturbs purifying and descending function of Lung and leading to runny or stuffy nose.