Tracking Allergy Triggers
People commonly blame allergies for a whole range of imprecise symptoms, from fatigue, weakness and headache to depression and anxiety or behavior problems such as hyperactivity. The popular saying “I’m allergic to this or that” – to the furniture, broccoli or a certain plant – ire n generic statement made without knowing or stopping to consider what an allergy really is.
The goal in diagnosing Allergies is to determine whether the reaction described is due to an allergic (immunological) response or to something else, mid to try to pinpoint the specific allergen(s) that bring on the discomfort.
One problem in diagnosing an allergy is the common confusion between allergy and toxicity. Whereas toxins (poisons) – for example, cyanide or rattlesnake venom – harm almost everyone, allergens affect only about 15 to 20 percent of the North American population, but for this minority something as everyday as peanuts or cod can be deadly even in trace amounts.
Further confusion arises from the term “sensitivity.” Some people are “sensitive” to (or dislike) the smell of garlic or a certain fragrance. That is not an allergic sensitivity. In allergic terms, “sensitivity” means that the immune system has been sensitized to a particular allergen and will react to it with a specific set of immunological changes. Although allergies can signal their presence in various ways and affect different parts of the body, an allergic reaction produces definite, reproducible and identifiable changes that can be evaluated — not vague, ill-defined complaints. Irritability, fatigue, anxiety, muscle aches, bedwetting and a host of other health problems frequently attributed to allergy are not immunological reactions — and not allergies.
Different Allergies Affect Different Body Sites
An allergic reaction can affect many parts of the body:
• nose and upper airways — causing a runny nose, stuffiness and sneezing;
• the lower bronchial passages (airways) and lungs — producing chest tightness, wheezing, breathlessness and (in asthma) a cough;
• the mouth and lips — which may tingle, itch, burn or swell;
• the throat — which may become inflamed and constricted, jeopardizing breathing;
• the eyes — which may become red, puffy, watery and itchy;
• the gastrointestinal tract — producing nausea, vomiting and diarrhea;
• the skin — which can develop a rash, hives or dry, scaling sores (as in eczema) and flushing;
• the entire body — with multiple systems affected, producing airway obstruction and a precipitous drop in blood pressure (depriving the heart and brain of oxygen) leading to allergic shock and anaphylaxis.
Classic Signs and Symptoms of Allergy
- Hives or a red, itchy rash
- sneezing, stuffy nose, clear nasal discharge
- puffy face
- red, watery eyes
- gut spasms, maybe nausea and vomiting
- burning, itchy mouth/lips
Severe, possibly heralding Anaphylaxis
• swelling of tongue, larynx (voice box)
• altered voice, difficulty speaking
• constricted throat, trouble swallowing
• labored breathing, wheezing
• sense of doom
• irregular heartbeat
• drop in blood pressure
• loss of consciousness
Distinguishing Allergies from Non-allergic Reactions
If someone suspects an allergy, the first step is usually a visit to the family physician to find out whether the symptoms arise from an immune-system reaction or are due to some other disorder. Since some symptoms of allergy mimic those of other conditions, it’s crucial to rule out other possibilities before diagnosing an allergy. Many intolerances and reactions to certain foods, drugs and other substances resemble but are not immunologically mediated reactions.
Adverse responses blamed on allergies often arise from non-immunological causes — perhaps a specific disease or even pregnancy, which is known to cause, hives, flushing and sneezing on occasion.
Physicians find that, in about half the cases investigated, the wheezing, runny eyes and nasal stuffiness don’t stem from an allergy but from some other disorder, such as sinusitis or an eye infection. Rhinitis (a perpetually stuffy nose) is due to an allergy in only about 70 percent of cases examined. Only about 10 to 20 percent of reactions attributed to specific foods are real allergies; the rest are food intolerances.
In a few instances, it may not be necessary to discover whether symptoms arise from an allergic or a non-allergic disorder to plan treatment. For example, a troublesome reaction to ASA (aspirin) requires the same strategy — avoidance — whatever the underlying mechanism. But distinguishing an allergic from a non-allergic reaction is usually essential for appropriate treatment. For example, to remedy milk intolerance due to lack of the enzyme lactase, the person can consume milk products to which the missing enzyme has been added to make them digestible.
But if the adverse symptoms stem from an allergy to cow’s milk protein, cow’s milk must be altogether avoided and replaced by a nutritionally sound substitute.
Allergy or not? Some telltale clues
- A clear discharge from a runny nose suggests allergy; a thick, colored discharge is more likely due to a viral or bacterial infection.
- Nasal itching and stuffiness around animals often indicate an allergy.
- Endless sneezing, nasal stuffiness and an itchy nose or red eyes at certain times of year suggest seasonal pollen or mold allergy.
- Mild, intermittent wheezing suggests allergy, particularly in preschoolers. Chronic asthma is allergy-linked in 50 percent of children over age six.
- Eczema that’s mild and patchy is probably not of allergic origin.
- Hives or swelling starting immediately after drinking milk or eating foods containing a common ingredient suggest a food allergy. Hives or swelling after eating a restaurant meal may stem from sensitivity to a flavor enhancer such as monosodium glutamate (MSG) or sulfite preservatives.
- If discomfort begins after certain medications are taken — such as antibiotics (especially penicillin, cephalosporins or sulfa drugs), arthritis medications or ASA (aspirin) — the problem may be a drug allergy.