New allergies can develop at any point in life, not just during childhood. The immune system is dynamic and adaptable, capable of changing its responses to various substances. This means individuals can acquire new sensitivities, even to things encountered without issue for many years.
How New Allergies Develop
Allergies begin with a process called sensitization, where the immune system mistakenly identifies a typically harmless substance, known as an allergen, as a threat. During the initial exposure, the immune system produces specific immunoglobulin E (IgE) antibodies. These IgE antibodies then attach to specialized immune cells, such as mast cells and basophils, preparing the body for a potential future reaction.
Upon subsequent exposure to the same allergen, these pre-sensitized mast cells and basophils rapidly release inflammatory chemicals, including histamine. Histamine is responsible for common allergy symptoms like itching, swelling, and inflammation. This immune response is an overreaction. New sensitivities can develop throughout a person’s life, influenced by genetic predispositions and environmental factors.
Factors Contributing to Adult-Onset Allergies
Several factors can contribute to the development of new allergies in adulthood. A change in geographic location, for instance, can introduce new types of pollen or environmental allergens an individual has never encountered before. Similarly, increased or prolonged exposure to a previously tolerated substance, such as acquiring a new pet or encountering chemicals in a new occupation, can lead to sensitivity.
Lifestyle and dietary changes may also play a role, including new foods or medications. Hormonal shifts, particularly in women, can influence immune function and contribute to new allergies. Pregnancy and menopause, for example, involve significant fluctuations in hormones like estrogen and progesterone, which can alter the immune system’s reactivity and histamine production. Periods of significant immune system modulation, such as severe illness, infections like COVID-19, or chronic stress, can also predispose an adult to developing new allergies by affecting immune regulation.
Identifying and Confirming New Allergies
Recognizing the signs of a new allergy often begins with observing consistent reactions after exposure to certain substances. Common symptoms can vary widely but may include skin rashes, hives, itching, swelling, respiratory issues like sneezing, a runny nose, or wheezing, and digestive problems such as stomach cramps or vomiting. Symptoms can range from mild discomfort to severe, potentially life-threatening reactions.
If a new allergy is suspected, seeking advice from a healthcare professional is advisable. They will typically gather a detailed medical history and perform a physical examination. To confirm a diagnosis, doctors may utilize specific tests like a skin prick test, where small amounts of potential allergens are applied to the skin to observe a reaction. Another common method is a blood test, which measures the levels of specific IgE antibodies in the blood, indicating sensitivity to particular allergens. Self-diagnosis or self-treatment is not recommended, as professional evaluation ensures accurate identification of the allergen and appropriate management strategies.