General: Allergy treatment depends on the severity of symptoms. Commonly used allergy medications include antihistamines, nasal sprays, decongestants, leukotriene inhibitors and allergen immunotherapy (allergy shots). Patients should tell their healthcare providers if they are taking any drugs (prescription or over-the-counter), herbs or supplements.
Short-acting antihistamines: Short-acting antihistamines like diphenhydramine (Benadryl®) have been used to relieve mild to moderate allergy symptoms. Most short-acting antihistamines are available over-the-counter. These medications often cause drowsiness, and many have shown to blunt learning in children (even in the absence of drowsiness). However, loratadine (Claritin®), which is available over-the-counter, does not cause drowsiness or affect learning in children.
Longer-acting antihistamines: Longer-acting antihistamines like fexofenadine (Allegra®) or cetirizine (Zyrtec®) are available by prescription for mild to moderate allergy symptoms. They cause less drowsiness than short-acting antihistamines, and they are equally effective. These medications usually do not interfere with learning. Side effects may include drowsiness, dry mouth, headache, sore throat, stomach pain, vomiting or diarrhea.
Nasal corticosteroid sprays: Nasal corticosteroid sprays can effectively relieve allergy symptoms in patients who are not responding to antihistamines. Commonly prescribed corticosteroid sprays include fluticasone (Flonase®), mometasone (Nasonex®) and triamcinolone (Nasacort AQ®). Side effects may include nosebleeds, burning in the nose, runny nose, bloody mucus in the nose, cough, upset stomach, vomiting, diarrhea or dizziness.
Decongestants: Decongestants may help relieve symptoms such as nasal congestion (stuffy nose). These drugs shrink the tissues and blood vessels in the eyes and nose that swell in response to contact with an allergen. Nasal decongestant sprays like oxymetazoline (Afrin®) should not be used more than twice daily for three consecutive days because rebound nasal congestion may result. Decongestants in pill form do not cause this effect.
Cromolyn sodium: Cromolyn sodium is available as a nasal spray (Nasalcrom®) for treating hay fever. Eye drop versions of cromolyn sodium are available for itchy, bloodshot eyes. Side effects may include sore throat, bad taste in the mouth, cough, stuffy nose, burning or itching in the nose, sneezing, headache or stomach pain.
Allergen immunotherapy (allergy shots): Allergen immunotherapy, also known as allergy shots, is often used to treat patients who suffer from severe allergies, or for those who experience allergy symptoms more than three months a year. Allergen immunotherapy involves injecting increasing amounts of a diluted allergen into a patient over several months.
There are two phases of immunotherapy -
the build-up phase and the maintenance phase. During the build-up phase, allergy shots are injected into the upper arm once or twice a week for several months (typically three to six months). The dose is gradually increased until the maintenance dose is reached. The maintenance phase begins once the effective therapeutic dose is reached. This dose is different for each patient because it depends on the patient's level of allergen sensitivity and their response to immunotherapy during the build-up phase. Once the maintenance dose is reached, the patient will continue therapy every two to four weeks for two to five years or more.
Butterbur: Good scientific evidence suggests that butterbur may effectively prevent allergic rhinitis (inflammation of the nose) in susceptible individuals. Comparisons of butterbur to prescription drugs such as fexofenadine (Allegra®) and cetirizine (Zyrtec®) have reported similar efficacy. Additional study is warranted before a strong recommendation can be made. Avoid if allergic or hypersensitive to Petasites hybridus or other plants from the Asteraceae/Compositae family (like ragweed, marigolds, daisies and chrysanthemums). Raw, unprocessed butterbur plant should not be eaten due to the risk of liver or kidney damage, or cancer. Avoid if pregnant or breastfeeding.
Unclear or conflicting evidence
Aromatherapy: Despite widespread use in over-the-counter agents and vapors, there is not enough scientific evidence to recommend use of eucalyptus oil as a decongestant-expectorant (by mouth or inhaled form). The available studies have been poor quality, and have used combination therapies or 1,8-cineole (eucalyptol), which is a component of eucalyptus. Further study is needed before a firm conclusion can be made.
Choline: Oral tricholine citrate (TRI) effectively relieved allergic rhinitis symptoms in one study. However, further research is needed before a firm conclusion can be made.
Ephedra: Preliminary research suggests that ephedrine nasal spray, a chemical in ephedra, may help treat symptoms of nasal allergies. Since ephedra taken by mouth can cause serious side effects, including heart attack, seizure and stroke, ephedrine nasal sprays should only be used in the nose. Additional research is needed before a firm conclusion can be made.
Probiotics: Only a small number of probiotic combinations have been studied for the treatment of allergies, mostly with children, teenagers and young adults. Further research is necessary before a firm conclusion can be made.
Stinging nettle: For many years, a freeze-dried preparation of Urtica dioica has been prescribed by physicians and sold over-the-counter for the treatment of allergic rhinitis. Clinical trials demonstrating statistical significance over placebo, and/or equivalence with other available treatments, are needed to support the use of nettle in the treatment of allergic rhinitis.
Vitamin E: Although thought to aid in reducing the nasal symptoms of allergies, vitamin E intake may not be effective. However, current evidence is limited, and more studies are needed before a firm conclusion can be drawn.
Cover the bed mattress and pillows in dust-proof or allergen-impermeable covers. Regularly change bed linens, including sheets and pillow covers.
Maintain low humidity levels inside the home. A dehumidifier or air conditioner may help keep humidity low.
Regularly wash toys, such as stuffed animals, as well as linens and clothing in hot water (130 to 140 degrees Fahrenheit) and dry thoroughly. Wash items cautiously because such hot temperatures can potentially cause burns.
Keep stuffed toys away from beds.
Use a damp moth or cloth to clean dust inside the house.
Vacuum carpets and fabric-covered furniture regularly to remove dust inside the house. Use a vacuum cleaner with a double-layered microfilter bag or a high-efficiency particulate hair (HEPA) filter.
Wood, linoleum or vinyl flooring, as well as leather furniture can reduce the number of dust mites in the home. Use blinds or washable drapes instead of heavy drapery, which can harbor dust mites.