Each spring, summer and fall, plants release tiny pollen grains to fertilize other plants of the same species. Most of the pollens that cause allergic reactions come from trees, weeds and grasses. These plants make small, light and dry pollen grains that travel by the wind. Grasses are the most common cause of allergy. Ragweed is a main cause of weed allergies. Other common sources of weed pollen include sagebrush, pigweed, lamb’s quarters and tumbleweed. Certain species of trees, including birch, cedar and oak, also produce highly allergenic pollen. Plants fertilized by insects, like roses and some flowering trees, like cherry and pear trees, usually do not cause allergic rhinitis.
Certain over-the-counter and prescription medicines may help reduce pollen allergy symptoms.
- Antihistamines come in pill, liquid or nasal spray form. They can relieve sneezing and itching in the nose and eyes. They also reduce a runny nose and, to a lesser extent, nasal stuffiness.
- Decongestants are available as pills, liquids, nasal sprays or drops. They help shrink the lining of the nasal passages and relieve nasal stuffiness. Use decongestant nose drops and sprays only on the short-term.
- Nasal corticosteroids are a type of nasal spray. They reduce inflammation in the nose and block allergic reactions. They are the most effective medicine type for allergic rhinitis because they can reduce all symptoms, including nasal congestion. Nasal corticosteroids have few side effects.
- Leukotriene receptor antagonists block the action of important chemical messengers (other than histamine) that are involved in allergic reactions.
- Cromolyn sodium is a nasal spray that blocks the release of chemicals that cause allergy symptoms, including histamine and leukotrienes. This medicine has few side effects, but you must take it four times a day.
Many people with pollen allergy do not get complete relief from medications. This means they may be candidates for immunotherapy. Immunotherapy is a long-term treatment that can help prevent or reduce the severity of allergic reactions. It can change the course of allergic disease by modifying the body’s immune response to allergens.
Allergy Shots – Subcutaneous Immunotherapy (SCIT) has been around for more than 100 years and can provide long-lasting symptom relief. SCIT is a series of shots that have progressively larger amounts of allergen. An injection of the allergen goes into the fat under the skin. Over time, allergic symptoms generally improve. Many patients experience complete relief within one to three years of starting SCIT. Many people experience benefits for at least several years after the shots stop.
Sublingual Immunotherapy involves placing a tablet containing the allergen under the tongue for 1 to 2 minutes and then swallowing it. In 2014, the FDA approved three types of under-the-tongue tablets to treat grass and ragweed allergies. More are in development. You take SLIT tablets daily before and during grass or ragweed season. This treatment offers people with these allergies a potential alternative to allergy shots.