New allergies can develop at any point in life, even if you’ve never had them before. This is known as adult-onset allergies, and it can be surprising for those who previously tolerated certain substances. Understanding how and why these reactions occur helps in recognizing and managing them.
The Reality of Adult-Onset Allergies
Adult-onset allergies are not uncommon and can affect individuals regardless of their age or prior allergic history. The immune system is constantly changing, and its responses to various substances can shift over time. These newly developed allergies can range in severity from mild discomfort to severe, potentially life-threatening reactions.
Reasons for New Allergies
The exact reasons for adult-onset allergies are not always clear, but several factors can contribute to their development. Changes in the immune system, possibly due to hormonal shifts like pregnancy or menopause, or the natural aging process, can make the body more sensitive to previously tolerated allergens.
New or increased exposure to allergens can also play a role. Moving to a new environment with different types of pollen, mold, or pollutants can introduce unfamiliar allergens. Similarly, a new pet or changes in diet can lead to increased exposure to pet dander or certain food proteins, triggering a new allergic response. Repeated exposure to an allergen may eventually push the immune system past its threshold, leading to symptoms. Genetic predispositions also influence susceptibility; if allergies run in your family, you may be more likely to develop them.
Common Allergies Emerging in Adulthood
Several types of allergies commonly emerge in adulthood. Food allergies are frequently reported, with common triggers including shellfish, tree nuts, peanuts, and fin fish. Some individuals may even develop an allergy to foods they have consumed for years. Drug allergies can also appear, often triggered by new or increased exposure to medications like antibiotics or pain relievers.
Environmental allergies, often called hay fever or allergic rhinitis, are also prevalent among adults. These include reactions to pollen from trees, grasses, and weeds, as well as indoor allergens like dust mites, mold spores, and pet dander. Oral Allergy Syndrome (OAS), or Pollen-Food Syndrome (PFAS), involves reactions to raw fruits, vegetables, or some tree nuts due to cross-reactivity with pollen allergens. Insect sting allergies, such as those to bee or wasp venom, can also develop later in life after multiple exposures.
Recognizing Symptoms and Seeking Medical Advice
The symptoms of adult-onset allergies can vary widely depending on the allergen and may sometimes be mistaken for other conditions. Mild symptoms include skin reactions such as hives, itchy rashes, or eczema. Respiratory symptoms can involve sneezing, nasal congestion, a runny nose, coughing, wheezing, or itchy, watery eyes. Food allergies may also present with digestive discomfort, including nausea, vomiting, abdominal pain, or diarrhea, or tingling in the lips, mouth, or tongue.
More severe reactions, such as anaphylaxis, can develop suddenly and are life-threatening. Signs of anaphylaxis include difficulty breathing, swelling of the face, lips, or tongue, a rapid heart rate, dizziness, or a sudden drop in blood pressure. If you experience new or worsening symptoms, especially those that are persistent or severe, seek medical advice. An allergist can perform tests, such as skin prick or blood tests, to identify the allergens triggering your reactions.