That's because your body misinterprets these harmless substances as dangerous and tries to get rid of them. Your immune system produces antibodies called Immunoglobulin E (IgE) specific to the trigger it’s trying to fight. These IgE antibodies tell other cells to release certain chemicals, including histamine. And it’s those chemicals that cause the annoying symptoms.
Hay fever caused by pollen is naturally dependent on the flowering season of the respective plants. Depending on the region and the climate, pollen is released from early spring, through the summer and even into the autumn. But you’re typically more likely to experience symptoms during late spring and early summer.
If you experience hay fever-like symptoms all year round, this might be perennial allergic rhinitis caused by an allergy to dust mites or pet dander. Talk to your health care provider about your symptoms to find out exactly what you’re allergic to and what possible treatments are available.