Allergies

Causes of Allergies:

Allergies come in many distinct forms and are typically grouped in general categories according to the types of substances that cause them or the parts of the body they affect.

Skin allergies: Contact dermatitis is caused by direct, topical exposure to a specific allergen; atomic dermatitis has no known cause, but it is usually hereditary. Hives, or urticaria, is an eruption of itchy, swollen, reddened welts that can last for minutes or days. Angioedema is characterized by a deeper swelling around the eyes and lips, and sometimes of the hands and feet as well. Both hives and angioedema stem from the body's adverse reaction to certain foods, pollen, animal dander, drugs, insect stings, cold, heat, light, or even emotional stress.

Respiratory allergies: Some 20 million Americans suffer from hay fever (allergic rhinitis). Typical symptoms include itchy eyes, nose, and roof of mouth or throat, along with nasal congestion, coughing, and sneezing. If you (or members of your family) have other allergies such as dermatitis or asthma, you are more likely to have hay fever. The terms allergic rhinitis and hay fever apply specifically to reactions caused by the pollens of ragweed, grasses, and other plants whose pollen is spread by the wind. But the same symptoms can be produced by other airborne substances that you inhale. These can include molds, dust, and animal dander. If, for example, you are allergic to cat dander (dead skin scales and saliva), being near a cat will make you sneeze, wheeze, and sniffle. Mold allergies are caused by airborne spores. Outdoor molds -- alternaria and hormodendrum -- thrive in warm seasons or climates, while indoor molds -- penicillin, aspergillus, mucor, and rhizopus -- grow year round in damp locations (basements and bathrooms, for example). Dust causes allergies because it harbors offenders such as pollen, mold spores, and microscopic dust mites; it may also contain irritating fibers from fabrics, upholstery, and carpets.

Asthma: Asthma has various causes, but the chief ones are environmental exposures and allergies to pollen, mold spores, animal dander, and dust mites.

Food allergies: An estimated 70% of people with food allergies are under 30; most are children under the age of 6. It is sometimes difficult to pinpoint the specific allergens responsible for a food allergy, because reactions are often delayed or may be caused by food additives or even by eating habits. However, approximately 90% of food allergies are caused by proteins in cow's milk, egg whites, peanuts, wheat or soybeans. Other common food allergens include berries, shellfish, corn, beans, yellow food dye No. 5, and gum arabic (an additive in processed foods). The classic symptoms of food allergies include stomach cramps, diarrhea, and nausea. In more severe cases, there may be vomiting, swelling of the face and tongue, and respiratory congestion, as well as dizziness, sweating, and faintness.

Diagnostic and Test Procedures

After taking a full family and personal medical history, your physician will ask you a series of questions about your exposure and reactions to various allergens to eliminate and identify your allergies' causes. You may be asked to keep track of potential allergens and your allergic reactions for a week to aid in diagnosis. After this, your physician will choose a testing method.

The most common test for respiratory, penicillin, insect sting, skin, and food allergies is a skin test. A small amount of the allergen is scratched into, or injected just underneath, the skin, and the physician watches for allergic symptoms. The symptoms -- swelling, itchiness, and redness -- generally appear within 20 minutes. Skin tests are not completely reliable, because if too much of the allergen is administered, even a nonallergic person may react. Also, extremely sensitive people may go into anaphylactic shock from skin tests. An alternative for respiratory allergies is RAST (radioallergosorbent test), which measures the levels in the bloodstream of the antibodies associated with allergies.

Treatment

The most certain treatment for allergies is to avoid the substances that trigger them, but this can be difficult. The basic medications for allergies are antihistamines, which counteract the histamine chemicals that cause the allergic reactions. Prescription corticosteroid drugs may also be used for severe symptoms. In emergency situations -- when anaphylactic shock occurs -- injections of epinephrine are used to dilate bronchial passages. Immunotherapy, or allergy desensitization shots, may cure some allergies by introducing small amounts of the offending allergens in order to help the body learn to deal with them.

Conventional Medicine

Skin allergies: Atopic and contact dermatitis can be treated with a variety of corticosteroids, usually hydrocortisone, either applied to the skin or sometimes taken by mouth. Hives and angioedema often need no medication, but severe cases may require prescription antihistamines, cimetidine, terbutaline, or oral corticosteroids.

Respiratory allergies: Hay fever is generally treated with over-the-counter antihistamines, but your doctor may prescribe other, more powerful drugs -- such as cromolyn -- if your symptoms are severe. The same treatments apply to other respiratory allergies, but if your symptoms are severe, your physician may prescribe corticosteroids, in nasal spray or oral form. Immunotherapy has a high success rate, curing 70% to 80% of people treated for respiratory allergies.

Food allergies: The best treatment for food allergies is avoidance. If your reactions to certain foods are irritating but not life-endangering, your doctor may prescribe antihistamines or topical creams to help relieve symptoms.

Drug allergies: The only effective treatment for drug allergies is avoidance. Skin rashes associated with drug allergies are generally treated with antihistamines; occasionally they are treated with oral or topical corticosteroids.

Insect sting allergies: Avoidance is the best treatment, but immunotherapy may cure insect sting allergies. If you are extremely allergic and likely to go into anaphylactic shock, your doctor will prescribe an emergency kit, which you must carry with you at all times. This kit contains a preloaded injection of epinephrine, a fast-acting drug that counters anaphylactic shock. Your doctor can show you how to use this properly.

Alternative Choices

Since allergies can be difficult to diagnose, and are in many cases incurable, alternative remedies for them have become quite popular. But if you have a severe allergy, or in case of an emergency, you must see a conventional physician.

Acupressure: To relieve symptoms associated with respiratory allergies, try Large Intestine Four, the highest spot of the area between the index finger and thumb; rub firmly for one minute, then repeat on the other hand. Do not use this point if you are pregnant. To fortify the immune system, firmly massage Triple Warmer Five, two finger widths from your wrist on the top of your forearm, specifically the area between the two arm bones.

Aromatherapy: To relieve nasal congestion, try mixing one drop of lavender (Lavandula officinalis) oil and one teaspoon of a carrier oil such as sweet almond or sunflower oil; massage into the skin around your sinuses once a day. Eucalyptus (Eucalyptus globulus), cedarwood, and peppermint (Mentha piperita) oils also act as decongestants; dab on a handkerchief and inhale.

Chinese Herbs: Ephedra (Ephedra sinica) acts like the decongestant epinephrine, which opens up the lungs' airways when breathing is difficult. But be careful: Large quantities of this herb are equivalent to large quantities of the drug epinephrine and can have serious side effects. Do not use ephedra if you have high blood pressure or heart disease. Prepare an infusion by combining 5 grams ephedra, 4 grams cinnamon (Cinnamomum cassia) sticks, 1.5 grams licorice (Glycyrrhiza uralensis), and 5 grams apricot seed (Prunus armeniaca); let steep in cold water, then bring to a boil. Strain and drink hot.

Herbal Therapies: Infusions of chamomile (Matricaria recutita), elder (Sambucus nigra) flower, eyebright (Euphrasia officinalis), garlic (Allium sativum), goldenrod (Solidago virgaurea), nettle (Urtica dioica), and yarrow (Achillea millefolium) have antimucus and anti-inflammatory effects.

Homeopathy: For a runny nose, itchy throat, and sneezing, a homeopathic practitioner might suggest Arsenicum album (6c); for chronic thick mucus, Pulsatilla (6c); for a runny nose, sore upper lip and itchy eyes, Allium cepa (6c).

Prevention

Respiratory allergies: Install a high-efficiency air cleaner to help remove pollen and mold spores, and use an air conditioner in your home and car during warm seasons to keep pollen out; regularly clean damp areas with bleach to kill molds. Consider hiring a special cleaning service to rid furniture and upholstery of dust mites. Isolate your pets and keep them outside as much as possible. Regular baths for your pet will help reduce dander.

Food allergies: Instead of dairy products, try tofu-based foods. Always check food labels for additives that are known allergens, such as yellow food dye No. 5 and gum arabic. When eliminating foods from your diet, be sure to find alternate sources of nutrients. For example, if you cannot eat dairy foods, choose other foods high in calcium or take calcium tablets.

Call Your Doctor If:

You have violent stomach cramps, vomiting, bloating, or diarrhea; this could point to a serious food or other allergic reaction or food poisoning.
Breathing becomes extremely difficult or painful; you may be experiencing an asthma episode, another serious allergic reaction or a heart attack. Get emergency medical treatment.
You suddenly develop skin welts, accompanied by intense flushing and itching; your heart may also be beating rapidly. These symptoms may indicate the onset of anaphylactic shock, an extremely serious allergic reaction. Get emergency medical treatment.