Conventional Treatment
Treatment for an allergy often begins with identifying the allergens that are causing the problem. There are several tests your physician may recommend to identify the particular allergens that are making your child's life miserable:

• Scratch testing consists of placing a small amount of diluted allergen on a lightly scratched area of skin. If a bump develops there within fifteen minutes, your child is probably allergic to that substance.

• Intradermal testing is done by injecting the skin with suspected allergens at timed intervals. A control injection (one containing no allergen) is also given. If an allergen produces a wheel (a red, itchy bump), your child is allergic to that substance. An intradermal test is more accurate than a scratch test, but there is a greater risk that a child might suffer a severe reaction.

• Blood testing (a radioallergosorbent test, or RAST) measures total and specific levels of IgE and IgG, which are antibodies produced by the body's immune system. An elevated level of either of these may indicate an allergic reaction to the substance being tested.

Once testing has been completed, treatment may be recommended. Antihistamines are the medications most commonly used for respiratory allergies. Antihistamines work by blocking the action of chemicals called histamines, which are produced by the body in reaction to the presence of an allergen. Histamines cause swelling and congestion of nasal passages and increased mucus production. By blocking their action, antihistamines diminish allergic symptoms. Brompheniramine (in Allerhist and Dimetane, among others), diphenhydramine (Benadryl), and chlorpheniramine (Chlor-Trimeton) are common over-the-counter antihistamines suggested for respiratory allergies. Prescription antihistamines include azatadine (Optimine, Trinalin), clemastine (Tavist), astemizole (Hismanal), promethazine (Phenergan), and terfenadine (Seldane). Terfenadine and astemizole are relatively new medications that have the benefit of not causing the drowsiness that other antihistamines do. Check with your doctor before giving your child an antihistamine. Some of these medicines are not recommended for children under two years of age.

Cromolyn sodium (Intel or Nasalcrom) is a prescription medication that can be taken as a nasal spray to prevent the symptoms of respiratory allergies. It works by coating the membranes of the nose and stabilizing the white blood cells so that they do not react to foreign substances. In some cases this drug can cause gastrointestinal upset or throat and nose irritation, but it usually produces few side effects and is generally considered safe because it is minimally absorbed into the bloodstream. Its major drawback is that it must be used consistently, six times a day, for at least two weeks before it begins to take effect.

Decongestants decrease nasal congestion and swelling by constricting the blood vessels in the nasal membranes, thus allowing the mucus to drain more effectively. Decongestants are available as pills, nasal drops, and nasal sprays. These include oxymetazoline (in Afrin, Dristan, Neo-Synephrine 12 Hour, Sinex, and others), phenylephrine (in Alconefrin, Allerest, Coricidin Decongestant Nasal Mist, Neo-Synephrine, and Vacon), phenylpropanolamine (found in many common over-the-counter formulas, including Bayer Children's Cold Tablets, Contac, Coricidin D, Ornex, Sine-Off, Sinutab, St. Joseph Cold Tablets for Children, and Triaminic), and pseudoephedrine (Cenafed, Neo-Fed, Novafed, Sudafed, or Sudrin). These medications have a number of common side effects, including restlessness and insomnia. Also, if a spray or drop form is used for more than three or four days in a row, it creates a dependency that results in a rebound—or worsening of symptoms--when the medicine is stopped. Check with your doctor before giving your child a decongestant. Some of these medicines are not recommended for children under two years of age.