Dr. Susan Waserman: Most food allergies start in childhood, but you’re right, they can develop at any time in a person’s life.

Factors that favour the development of food allergy in adults include sensitization to pollens and house dust mites, as well as occupational sensitization (which occurs when people who regularly handle and inhale food become sensitized to it due to repeated exposures).

As well, adults with birch pollen allergy may develop “oral allergy syndrome,” which leads those affected to experience itchy mouth when they eat certain raw fruits and vegetables. This is the result of cross-reactivity between the food and the pollen.

Interestingly, those sensitized to house dust mites may end up with shrimp allergy because both contain the protein tropomyosin.

Occupational sensitization is also associated with crab and pork allergies.

Dr. Susan Waserman is an allergist and Professor of Medicine in the Division of Allergy and Clinical Immunology at McMaster University in Hamilton, Ont. She is also a past president of the Canadian Society of Allergy and Clinical Immunology.

We welcome your question to Allergic Living’s Ask the Allergist. Thank you for understanding that the specialists aren’t able to answer every question received.

Dr. Waserman: Daffodils are considered “allergy-friendly,” since plants with showy flowers are generally pollinated by insects rather than the wind. Daffodils produce less pollen, and symptoms such as allergic rhino-conjunctivitis and asthma aren’t commonly associated with them.

However – handling daffodils is another story. Among florists and flower pickers, allergic contact dermatitis, irritant contact dermatitis (from sap) and hives are quite common.

Your daughter may have had an allergic or irritant contact dermatitis reaction or urticaria (hives). I recommend that she not handle daffodils and related narcissus varieties.

While unusual with daffodils, the throat symptoms might be an acute reaction, or anxiety as you suggest. Your daughter needs to be assessed by an allergist. If her symptoms and testing indicate allergic rhinitis, the allergist likely will prescribe intranasal steroids to alleviate the allergy.

We welcome your question to Allergic Living’s Ask the Allergist. Thank you for understanding that the specialists aren’t able to answer every question received.

Dr. Susan Waserman is an allergist and Professor of Medicine in the Division of Allergy and Clinical Immunology at McMaster University in Hamilton, Ont. She is also a past president of the Canadian Society of Allergy and Clinical Immunology.

Dr. Waserman: What you are describing is a common occurrence called the “September peak”. This was the subject of a recently published study in which researchers showed an increase in emergency department visits, hospital admissions and doctor visits for childhood asthma in September, all related to the return to school.
The common cold virus, called rhinovirus, is likely the major trigger. Also, the low use of asthma medications during the summer months likely contributes to the problem. Might this be so in your son’s case?

The good news is that the research also showed that the addition of an effective asthma controller medication before the start of school appeared to prevent this. In the study Montelukast (Singulair) was prescribed, speak to your doctor about what’s best to use for your son and whether his asthma action plan might need an adjustment.

We welcome your question to Allergic Living’s Ask the Allergist. Thank you for understanding that the specialists aren’t able to answer every question received.

Dr. Susan Waserman is an allergist and Professor of Medicine in the Division of Allergy and Clinical Immunology at McMaster University in Hamilton, Ont. She is also a past president of the Canadian Society of Allergy and Clinical Immunology.

Dr. Waserman: Having allergic parents does place your son at higher risk of becoming allergic. However the particular allergies he may develop are not predictable.

Even though you are breastfeeding, unless you have been on milk avoidance yourself, he has probably already been exposed. I would introduce milk at the recommended time.

A cautious way to do so would be to place a drop on your son’s face, wait 10 minutes to see if he develops any redness or swelling,  and then increase to two drops on his lip, also waiting and observing for any reaction.

You can then slowly increase his exposure over 1-2 days. If you are anxious, skin testing by an allergist to determine his allergic status can also be done. It will delay the process, but will let you know one way or another. Good luck!

We welcome your question to Allergic Living’s Ask the Allergist. Thank you for understanding that the specialists aren’t able to answer every question received.

Dr. Susan Waserman is an allergist and Professor of Medicine in the Division of Allergy and Clinical Immunology at McMaster University in Hamilton, Ont. She is also a past president of the Canadian Society of Allergy and Clinical Immunology.

Dr. Waserman: Oral allergy syndrome is seen in birch tree or ragweed pollen allergic individuals  who may develop symptoms on ingestion of certain raw fruits, vegetables, or tree nuts.

Symptoms typically consist of itching, tingling or  swelling of the mouth, lips, and throat. An allergic reaction happens when the foods are eaten raw. Once the foods are cooked, they can be eaten safely.

Jams are prepared by heating the particular fruit. If you experienced symptoms after peach jam, you may have a true food allergy to peach, and not just an oral allergy syndrome. I highly recommend consultation with an allergist for assessment and skin testing to help sort this out.

We welcome your question to Allergic Living’s Ask the Allergist. Thank you for understanding that the specialists aren’t able to answer every question received.

Dr. Susan Waserman is an allergist and Professor of Medicine in the Division of Allergy and Clinical Immunology at McMaster University in Hamilton, Ont. She is also a past president of the Canadian Society of Allergy and Clinical Immunology.