Allergic rhinitis is caused by allergens, which are usually harmless substances but trigger an allergic reaction in some people.

People with rhinitis are prone to symptoms such as runny nose, sneezing, congestion and sinus pressure. Rhinitis can contribute to other problems such as asthma, sinus or ear conditions or trouble sleeping.

Seasonal allergic rhinitis, often referred to as hay fever, is typically caused by outdoor allergens such as pollen from trees, grasses and weeds.

Perennial allergic rhinitis occurs year-round. It is usually triggered by allergens such as pets or dust mites.

Some people with rhinitis symptoms don’t suffer from allergies. The symptoms may be similar, but the causes are different. Strong odors, pollution, smoke and other irritants may cause symptoms of non-allergic rhinitis. Medications and other chronic health conditions can also contribute to non-allergic rhinitis symptoms.