In general, there is no cure for allergies, but there are several types of medications available -- both over-the-counter and prescription -- to help ease and treat annoying symptoms like congestion and runny nose. These allergy drugs include antihistamines, decongestants, combination drugs, corticosteroids, and others.
Allergy shots, which gradually increase your ability to tolerate allergens, are also available.
Antihistamines have been used for years to treat allergy symptoms. They can be taken as pills, liquid, nasal spray, or eye drops. Over-the-counter (OTC) antihistamine eye drops can relieve red itchy eyes, while nasal sprays can be used to treat the symptoms of seasonal or year-round allergies.
Examples of antihistamines include:
- Over-the-counter: bromepheniramine (Dimetapp allergy, Nasahist B), cetirizine (Zyrtec), chlorpheniramine (Chlor-Trimeton), clemastine (Tavist), diphenhydramine (Benadryl), fexofenadine (Allegra), and loratadine (Claritin, Alavert). Pheniramine (OcuHist) is an eye drop.
- Prescription: Clarinex and Xyzal are oral medications. Astelin is a prescription nasal antihistamine spray. Prescription antihistamine eye drops include Patanol and Elestat and Optivar.
How Do Antihistamines Work?
When you are exposed to an allergen -- for example ragweed pollen -- it triggers your immune system. People with allergies demonstrate an exaggerated immune response. Immune system cells known as "mast cells" release a substance called histamine, which attaches to receptors in blood vessels, causing them to enlarge. Histamine also binds to other receptors causing redness, swelling, itching, and changes in secretions. By blocking histamine and keeping it from binding to receptors, antihistamines prevent these symptoms.
What Are the Side Effects of Antihistamines?
Many older over-the-counter antihistamines may cause drowsiness. Newer, non-sedating second- and third-generation antihistamines are available over-the-counter or by prescription.
Decongestants relieve congestion and are often prescribed along with antihistamines for allergies. They can come in nasal spray, eye drop, liquid, or pill form.
Nasal spray and eye drop decongestants should be used for only a few days at a time, because long-term use can actually make symptoms worse. Pills and liquid decongestants may be taken longer safely.
Some examples of decongestants that are available over-the-counter include:
- pseudoephedrine (Sudafed tablets or liquid, Actifed), phenylephrine (Neo-Synephrine) and oxymetazoline (Afrin) nasal sprays, and some Visine eye drops
How Do Decongestants Work?
During an allergic reaction, tissues in your nose may swell in response to contact with the allergen. That swelling produces fluid and mucous. Blood vessels in the eyes can also swell, causing redness. Decongestants work by shrinking swollen nasal tissues and blood vessels, relieving the symptoms of nasal swelling, congestion, mucus secretion, and redness.
What Are the Side Effects of Decongestants?
Decongestants may raise blood pressure, so they typically are not recommended for people who have blood pressure problems or glaucoma. They may also cause insomnia or irritability and restrict urinary flow.
Combination Allergy Drugs
Some allergy drugs contain both an antihistamine and a decongestant to relieve multiple allergy symptoms. Other drugs have multiple effects aside from just blocking the effects of histamine, such as preventing mast cells from releasing other allergy-inducing chemicals.
Some examples of combination allergy medicines include:
- Over-the-counter: cetirizine and pseudoephedrine (Zyrtec-D), fexofenadine and pseudoephedrine (Allegra-D), diphenhydramine and pseudoephedrine (Benadryl Allergy and Sinus), loratadine and pseudoephedrine (Claritin-D) for nasal allergies; ketotifen (Zaditor) and naphazoline/pheniramine (Naphcon A) for allergic conjunctivitis
- Prescription: acrivastine and pseudoephedrine (Semprex-D) for nasal allergies; azelastine (Optivar) and olopatadine (Patanol) for allergic conjunctivitis; azelastine/fluticasone (Dymista) combines an antihistamine with a steroid in a nasal spray for seasonal nasal allergies
Steroids, known medically as corticosteroids, can reduce inflammation associated with allergies. They prevent and treat nasal stuffiness, sneezing, and itchy, runny nose due to seasonal or year-round allergies. They can also decrease inflammation and swelling from other types of allergic reactions.
Systemic steroids are available in various forms: as pills or liquids for serious allergies or asthma, locally acting inhalers for asthma, locally acting nasal sprays for seasonal or year-round allergies, topical creams for skin allergies, or topical eye drops for allergic conjunctivitis. In addition to steroid medications, your physician may decide to prescribe additional types of medications to help combat your allergic symptoms.
Steroids are highly effective drugs for allergies, but they must be taken regularly, often daily, to be of benefit -- even when you aren't feeling allergy symptoms. In addition, it may take one to two weeks before the full effect of the medicine can be felt.
Some steroids include:
- Prescription nasal steroids: beclomethasone (Beconase, Qnasl), ciclesonide (Zetonna) fluticasone proprionate (Flonase), fluticasone furoate (Veramyst), and mometasone (Nasonex)
- Over-the-counter nasal steroids: budesonide (Rhinocort Allergy), fluticasone (Flonase Allergy Relief), and triamcinolone (Nasacort Allergy 24HR)
- Inhaled steroids : beclomethasone (QVar), budesonide (Pulmicort), ciclesonide (Alvesco), flunisolide (Aerobid), fluticasone (Flovent), mometasone (Asmanex) and triamcinolone (Azmacort) are used to treat asthma. Budesonide/formoterol (Symbicort) and fluticasone/salmeterol (Advair) are inhaled drugs called bronchodilators that combine a steroid with another drug to treat asthma. Inhaled steroids are available only with a prescription.
- Eye drops: dexamethasone (Dexamethasone Ophthalmic), and loteprednol (Alrex)
- Oral steroids: Deltasone, also called prednisone
What Are the Side Effects of Steroids?
Steroids have many potential side effects, especially when given orally, systemically, and for a long period of time.
Side effects of systemic steroids with short-term use include:
Potential systemic steroid side effects with long-term use include:
Side effects of inhaled steroids may include cough, hoarseness, or fungal infections of the mouth.
Bronchodilators are inhaled drugs used to control asthma symptoms and are available only with a prescription. A short-acting bronchodilator is used to provide quick relief for asthma symptoms during an attack. Long-acting bronchodilators can provide up to 12 hours of relief from asthma symptoms, which is helpful to people who suffer from nighttime asthma problems.
How Do Bronchodilators Work?
Bronchodilators relax the muscle bands that tighten around the airways. This rapidly opens the airways, letting more air in and out of the lungs, improving breathing.
Bronchodilators can also help clear mucus from the lungs. As the airways open, the mucus can move more freely and is then more easily expelled.
Generally, 1-4 puffs of an inhaler relieve the wheezing and chest tightness associated with a mild attack. It may be necessary to take more puffs for severe attacks. You should speak with your health care provider about developing an asthma plan.
Some types of bronchodilators include:
- Albuterol (Ventolin, Proventil, Pro-Air)
- Levalbuterol (Xopenex)
What Are the Side Effects of Bronchodilators?
Bronchodilators are potent drugs. If overused, they can cause dangerous side effects such as high blood pressure and a fast heartbeat.
Mast Cell Stabilizers
Mast cell stabilizers can be used to treat mild to moderate inflammation in the bronchial tubes and other allergy symptoms. These medications can also be used to prevent asthma symptoms during exercise and can be given before exposure to an allergen when it cannot be avoided.
Mast cell stabilizers are available as inhalers for asthma, eyedrops for allergic conjunctivitis, and nasal sprays for nasal allergy symptoms. Like with many drugs, it may take several weeks before the full effects are felt.
Some examples of mast cell stabilizers include:
- Cromolyn sodium (Intal)
- Lodoxamide (Alomide)
- Nedocromil (Alocril)
How Do Mast Cell Stabilizers Work?
Mast cell stabilizers work by preventing the release of histamine from mast cells (cells that make and store histamine). Some of these drugs also have important anti-inflammatory effects, but typically they are not as effective as steroids.
What Are the Side Effects of Mast Cell Stabilizers?
Throat irritation, coughing or skin rashes sometimes can occur with inhaled mast cell stabilizers. Mast cell stabilizers in the form of eye drops may cause burning, stinging, or blurred vision when they are administered.
Leukotriene modifiers are used to treat asthma and nasal allergy symptoms. They can be prescribed along with other drugs.
These medications are available only with a doctor's prescription and come as pills, chewable tablets, and oral granules.
Examples of leukotriene modifiers include:
- Monteleukast (Singulair)
- Zafirlukast (Accolate)
- Zyflo (zileuton)
How Do Leukotriene Modifiers Work?
Leukotriene modifiers block the effects of leukotrienes, chemicals produced in the body in response to an allergic reaction.
What Are the Side Effects of Leukotriene Modifiers?
Side effects of these drugs are rare, especially for Accolate and Singulair, but may include:
- Stomach pain or stomach upset
- Stuffy nose
- Behavioral issues
Other Over-The-Counter Products
Some simple over-the-counter products can help with allergy symptoms. They include:
- Saltwater solution, or saline, is available as a nasal spray to relieve mild congestion, loosen mucus, and prevent crusting. These sprays contain no medicine.
- Artificial tears, which also contain no medicine, are available to treat itchy, watery, and red eyes.
Immunotherapy, or allergy shots, may be the most effective form of treatment if you suffer from allergies more than three months of the year. These shots expose you to gradually increasing levels of the offending allergen to help your immune system build tolerance.
Also, the FDA has approved three under-the-tongue tablets that can be taken at home. The prescription tablets, called Grastek, Ragwitek, and Oralair, are used for treating hay fever and work the same way as shots -- the goal is to boost a patient’s tolerance of allergy triggers.