Dear Dr. Samson,
I have a 9-month-old infant and I'm introducing new foods to his diet. I assume symptoms of food allergies can be diarrhea and vomiting. What other symptoms can food allergies cause?
Diarrhea and vomiting are only the tip of the food-allergy iceberg. Many parents assume that foods cause only intestinal trouble.
Since a reaction to a food may be a generalized reaction, any system can be affected. Specifically, signs and symptoms of food sensitivity may be any one or a combination of the following list: hives, eczema, coughing, wheezing, runny nose, ear infection, itchy eyes, fatigue, irritability, recurrent infections, stomach cramps, headache, sleeplessness, hyperactivity, depression and of course vomiting or diarrhea.
The following case examples will emphasize the variability of symptoms:
Jody, a 6-year-old girl had proven to be a difficult child in school. She was overactive and easily distracted. At home she was becoming a real behavior problem. Interestingly, she was not so in kindergarten. The usual evaluation revealed no cause. For completeness we evaluated her for any food allergies. Tests were negative except for a positive reaction to peanuts. It was then that the plot thickened. The mother recalled that since first grade necessitated a packed lunch, the mainstay of Jody's midday meal became a peanut butter sandwich. Prior to this her contact with peanut butter was nil. I suggested we remove all peanut products from her diet. Within four weeks Jody had returned to her past lovely self. Having some doubts to this we reintroduced the peanut product and within 72 hours she was transformed into her "Mr. Hyde" personality. Peanut butter was again removed and all was well. At this point the parents and I were convinced there was a relationship between Jody's eating peanut butter and her behavior. One of the relatives apparently was not as convinced and on her own, during baby-sitting stints, repeatedly gave Jody peanut butter. Again the behavior recurred. I must add, it was confusing because it took time to ferret out the source of peanuts. She remained in the area for two years and then moved. I can't tell you if she still is sensitive but she was until she left.
Kathy was a 3-year-old girl who developed sleeping problems. Some nights she would scream and cry, not really being awake. She was unconsolable. It did not occur on a daily basis. Careful history taking revealed that she had been allergic to cow's milk as an infant and was not drinking milk when the sleep disturbance started but was allowed to have ice cream occasionally. The nights following ice cream treats were the ones disturbed. Several documented challenges proved the cause-and-effect relationship. With a dairy-free diet she slept like an angel. This same patient is now 6 years old and as you might guess did some self experimenting with ice cream at school. This time her sleep was not disturbed, but she developed hard, tender, red bumps on her skin within 24 yours of her ice cream challenges.
The last case example involves Joshua, an 18-month-old boy. He moved to Long Beach with a history of coughing and wheezing from age six months. Medication did not really help. He was free of diarrhea and was large for his age. The mother remembered she had started cow's milk at six months of age when she stopped breast feeding. This was the lead we needed to remove dairy products from his diet. Within two weeks he was free of the respiratory symptoms. One of his grandmothers, being a believer that babies need milk, gave him dairy products. Yes, you guessed it, the cough and wheeze returned. Until we traced the source of cow protein we thought a new allergen had developed. Two years later he tolerates all dairy products without trouble.
The cases point out the variability of symptoms from person-to-person and from time-to-time. Always consult your child's doctor if unexplained chronic or recurrent symptoms are noted emanating from any body system. Don't assume the system in contact with the allergen is the only system that will react.