Allergy Medications

Antihistamines

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 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: Benadryl, Claritin, Chlor-Trimeton, Dimetane and Tavist. Ocu-Hist is an OTC eye drop.
• Prescription: Clarinex, Allegra, and Zyrtec. Astelin is a prescription nasal spray. Eye drops include Emadine and Livostin.

How Do Antihistamines Work?

When you are exposed to an allergen -- like ragweed pollen -- it triggers your immune system to go into action. 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 receptors, antihistamines prevent these symptoms.

What Are the Side Effects?

Many over-the-counter antihistamines cause drowsiness. Non-sedating antihistamines are available by prescription.

Decongestants

Decongestants relieve congestion and are often prescribed along with antihistamines. They come in nasal spray, eye drop, liquid or pill form.

Nasal spray and eye drop decongestants can be used for only a few days, since long-term use can actually make symptoms worse. Pills and liquid decongestants may be taken longer safely.

Some examples of decongestants include:

• Over-the-counter: Sudafed tablets or liquid, Neo-Synephrine and Afrin nasal sprays, and Visine eye drops.
• Prescription: Prescription decongestants include drugs like Claritin-D, Allegra-D and Zytec-D that combine a decongestant with another allergy medicine.

How Do Decongestants Work?

During an allergic reaction, tissues in your nose swell in response to contact with the allergen. That swelling produces fluid and mucous. Blood vessels in the eyes also swell, causing redness. Decongestants shrink swollen nasal tissues and blood vessels to relieve the symptoms of nasal swelling, congestion, mucous secretion and redness.

What Are the Side Effects?

Decongestants may raise blood pressure, so they are not recommended for people who have blood pressure problems or glaucoma. They may also cause insomnia or irritability and restrict urinary flow.

Combination Medicines

Some allergy medicines contain both an antihistamine and a decongestant to relieve multiple symptoms. There are also other combinations, such as those between an allergy medicine and asthma medicine and an antihistamine eye drop with a mast cell stabilizer drug (see below).

Some examples of combination medicines include:

• Over-the-counter: Benadryl Allergy and Sinus, Tylenol Allergy and Sinus.
• Prescription: Allegra-D, Claritin-D, Semprex-D,and Zyrtec-D for nasal allergies. Naphcon, Vasocon, Zaditor, Patanol and Optivar for allergic conjunctivitis.

Steroids

Steroids, known medically as corticosteroids, 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.

Steroids are available as pills, for serious allergies or asthma, inhalers, for asthma, nasal sprays, for seasonal or year-round allergies, creams, for skin allergies or as an eye drop, for allergic conjunctivitis. Your doctor may prescribe a steroid in addition to other allergy medications.

The drugs are highly effective, but they must be taken daily to be of benefit -- even when you aren't feeling symptoms. In addition, it may take one to two weeks before the full effect of the medicine can be felt.

Some steroids include:

• Nasal steroids: Beconase, Flonase, Nasocort, Nasonex, Rhinocort , and Veramyst used to treat nasal allergy symptoms.
• Inhaled steroids: Azmacort, Beclovent, Flovent, and Pulmicort used to treat asthma. Advair is an inhaled drug that combines a steroid with another drug to treat asthma. Inhaled steroids are available only with a prescription.
• Eye drops: Alrex and Dexamethasone
• Oral steroids: Deltasone, also called prednisone.

What Are the Side Effects?

Steroids have many potential side effects, especially when given orally and for a long period of time.

Side effects with short-term use include:

• Weight gain
• Fluid retention
• High blood pressure

Side effects with long-term use include:

• Growth suppression
• Diabetes
• Cataracts of the eyes
• Bone thinning osteoporosis
• Muscle weakness

Side effects of inhaled steroids include cough and yeast infections of the mouth.

Bronchodilators

Bronchodilators are inhaled medicines 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 also help clear mucus from the lungs. As the airways open, the mucus moves more freely and can be coughed out more easily.

Generally one or two puffs of the inhaler relieve the wheezing and chest tightness associated with a mild attack. It may be necessary to take more puffs for severe attacks.

Some types of bronchodilators include:

• Ventolin, Proventil
• Brethaire
• Tornalate
• Xopenex
• Alupent, Metaprel
• Maxair

What Are the Side Effects?

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 symptoms of allergic reactions. 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 many drugs it may take several weeks before the full effects are felt.

Some examples of mast cell stabilizers include:

• Intal
• Tilade
• Crolom
• Alomide
• Alocril
• Opticrom
• Alamast
• Nasalcrom

How Do Mast Cell Stabilizers Work?

Mast cell stabilizers work by stopping the release of histamine from mast cells (cells that make and store histamine). Some of these drugs also have important anti-inflammatory effects.

What Are the Side Effects?

Throat irritation, coughing or skin rashes sometimes can occur with inhaled treatment. Some people say that Tilade has a bad taste. Using a spacer to take the medicine and drinking juice following treatment may decrease the taste. Eye drops may cause burning, stinging or blurred vision.

Leukotriene Modifiers

Leukotriene modifiers are used to treat asthma and nasal allergy symptoms. They can be prescribed along with other medications.

These medications are available only with a doctor's prescription and come as pills, chewable tablets, and oral granules.

The brand names include:

• Accolate
• Singulair
• Zyflo

How Do They Work?

Leukotriene modifiers block the effects of leukotrienes, chemicals produced in the body in response to an allergy.

What Are the Side Effects?

• Stomach pain or stomach upset
• Heartburn
• Fever
• Stuffy nose
• Cough
• Rash
• Headache

Other Over-The-Counter Medications

• Salt-water 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

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. See our full article on allergy shots for more information.

From http://www.webmd.com/allergies/guide/allergy-medic