Q: I’d been led to understand that you had to have hives to have an allergic reaction, but my daughter, who’s 14, has come through an anaphylactic reaction to nuts (she ate a food product that turned out to contain cashews). She was nauseated, wheezing and the ER said her blood pressure dropped low. But not a hive on her. How unusual is it not to see hives?
Dr. Sicherer: It is a misconception that allergic reactions have to include hives. Although hives will be present in over 80 percent of allergic reactions, it is possible to have severe reactions without them. A lack of hives during anaphylaxis is a know risk factor for fatal anaphylaxis, likely for the very reason that treatment with epinephrine is delayed when anaphylaxis is not promptly identified.
It can be tricky to recognize anaphylaxis without hives. The most important point to understand is that anaphylaxis can happen without hives or rashes. When there is a possible or known exposure to an allergen, be on the lookout for:
- Breathing symptoms — shortness of breath, wheeze, repetitive cough, throat tightness, etc.
- Circulation symptoms — paleness, light-headedness, confusion, weak pulse, etc.
- Other signs — such as itchiness or feeling of doom.
The presence of some of these symptoms should be a tip-off that anaphylaxis is happening, that epinephrine should be injected promptly, and that 911 needs to be called to take the allergic person to hospital.
Dr. Scott Sicherer is Chief of the Division of Allergy and Immunology of the Jaffe Food Allergy Institute at the Icahn School of Medicine at Mount Sinai in New York. Together with Dr. Hemant Sharma, Associate Chief of the Division of Allergy and Immunology at Children’s National Medical Center in Washington, he writes “The Food Allergy Experts” column in the American Edition of Allergic Living magazine. Questions submitted below will be considered for answer in the magazine.