Steven M. Houser MD
Rhinology/Allergy pages
Food Allergy
Food allergies/sensitivities may be producing, or accentuating, your symptoms. This aspect of allergy is poorly understood in comparison to inhalant allergy (e.g., ragweed or dust mite). In order to diagnose and treat this aspect of your disease we will require a great deal of cooperation and work on your part. Allow us to briefly explain some of what we know about food allergies.
Food allergies are classified as being either fixed or cyclic. A fixed food allergy may be very apparent; e.g., the person whose lips swell and throat itches immediately in response to eating peanuts. The mechanism for this type of food allergy is similar to that of inhalant allergies, so the diagnosis is more easily reached. Blood testing (i.e., RAST test) is typically used to verify fixed food allergies. Approximately 5 to 15% of food allergies are of the fixed variety.
The more common cyclic food allergies are less well understood. The immunologic method producing these reactions are not the same as for fixed food allergies, and are poorly explained. Clinical experience though, has taught us to recognize and treat cyclic food allergies.
The symptoms which a patient experiences with a cyclic food allergy are highly variable. The patient may describe headaches, sinus pressure, rhinitis, abdominal cramping, skin eruptions, or fatigue to name a few. To complicate the situation further, the symptoms may occur in a delayed fashion up to 24 hours after the food is ingested.
To set about diagnosing and treating cyclic food allergy we ask the patient to do a number of things. First ask yourself, �are there any foods which I crave, or any food which I avoid at all costs?� These foods may be the ones which are causing your difficulties.
The next step is to keep a detailed food diary which keeps track of what was eaten (including ingredients), when it was eaten, medications taken, and any symptoms which developed (with time noted as well; see the fictional example below). When you are writing down your entire diet, people often change their diet to look healthier than it typically is. Please try to maintain your normal diet; no one will judge you based on what you are eating. You can be helped most easily if your diet records are both accurate, timed precisely, and truthful. Your diet diary can be evaluated by a physician (typically an otolaryngic allergist) to identify to identify one, or several, food items which may be the culprits.
You will be asked to perform an unblinded elimination and challenge diet at home based upon an interpretation of your diet diary. It is best if your carefully maintain a diet diary during the period of elimination and challenge. You must abstain from one, and only one, of the possible culprits at a time for a period of four days. This can be difficult to carry out if the food is very common, such a egg or wheat, so you need to pay strict attention to your diet during the elimination phase. Any �cheating� during the elimination will invalidate the results.
You will then eat the food on the fifth day; this is considered the challenge. Typically, your lunch will include an average sized portion of the food in question to be eaten in 5 minutes. In one hour you should ingest another 1/2 portion if no symptoms have developed. Any symptoms which develop are timed and recorded. With a true cyclic food allergy we would expect a significant exacerbation of the symptoms which were described in the original diet diary, although the challenge symptoms may vary as well. Fixed food allergies should never be deliberately challenged unless under the direct supervision of a physician. For minor, moderate discomfort from the testing the patient may take: 1) laxatives to decrease the transit time, 2) Alka Seltzer Gold, 3) Buffered Vitamin C (one gram).
If the elimination and challenge confirms a cyclic food allergy, then you will be asked to abstain from this food for a period of three to six months. After this time you can slowly reintroduce the food on a rotary basis; it is not to be eaten more frequently than every four days (once or twice a week).
Time Food eaten Meds Symptoms
6:30am orange juice, Allegra
toast with butter
10:am Fritos,
Pepsi headache, nausea
12noon Ham, cheddar cheese,
mustard, wheat bread,
Coke, fries (vegetable oil)
The sites listed below have additional information re: food allergies