Your body can get used to allergies, but how this happens and how well it works depends on the type of allergy, your age, and whether the process occurs naturally or with medical help. Some people notice their symptoms fade after years of exposure to a trigger, while others need structured treatment to shift their immune response. Children, in particular, frequently outgrow certain food allergies entirely. But “getting used to” an allergy is not one thing. It ranges from a temporary suppression of symptoms to a permanent rewiring of immune function.
How Your Immune System Learns to Stop Overreacting
An allergic reaction is your immune system treating a harmless substance like a threat. It produces a specific type of antibody (IgE) that triggers inflammation, sneezing, hives, or worse every time you encounter that trigger. When your body “gets used to” an allergen, the underlying immune machinery actually changes.
The shift involves two key things. First, your body starts producing different antibodies, particularly IgG4 and IgA, that act as blockers. These intercept the allergen before it can bind to the antibodies that cause symptoms. Over time, the original allergy-driving antibodies decline. Second, your immune system creates more regulatory T cells, which are specialized cells that calm down the overactive allergic branch of immunity. These cells release chemical signals that suppress inflammation and gradually retrain the immune response from one that attacks harmless proteins to one that ignores them.
This process also physically reduces the number of mast cells and other reactive cells in your nose, lungs, skin, or gut. Fewer reactive cells means less histamine release and milder symptoms, even when you’re exposed to the same amount of allergen.
Desensitization vs. True Tolerance
There’s an important distinction between two types of “getting used to” allergies. Desensitization is a temporary state where your body stops reacting, but only as long as you keep being exposed to the allergen. If exposure stops, symptoms return. True clinical tolerance means your immune system has permanently reset. You can go months or years without encountering the allergen, and when you do, nothing happens.
Most allergy treatments achieve desensitization rather than full tolerance. Someone receiving allergy shots for grass pollen, for example, may do well for years, but if they stop treatment prematurely, their symptoms often come back. True tolerance is harder to achieve and takes longer, but it does happen, especially in children with food allergies and in adults who complete a full course of immunotherapy.
Children Often Outgrow Food Allergies
Kids have the best odds of naturally getting used to their allergies. The rates vary dramatically by food. Cow’s milk allergy resolves in roughly 50% of children by age 5 in U.S. studies, climbing to about 79% by age 16. Egg allergy follows a similar pattern: around 50% of kids outgrow it by age 3, and about 68% by age 16. Soy allergy resolves in half of children by age 7, and wheat allergy in over half by age 8.
Peanut and tree nut allergies are a different story. Only about 22% of children outgrow peanut allergy by age 4, and just 29% by age 6. Tree nut allergies resolve in only 9 to 14% of cases. Shellfish allergy is the most persistent, with under 4% of children outgrowing it even after 5 to 10 years. If your child has a milk or egg allergy, the odds are genuinely in their favor. For peanut or tree nut allergies, natural resolution is much less likely, and medical intervention may be worth discussing.
Allergy Shots and Drops
Allergen immunotherapy is the most established way to train your body to tolerate an allergen. It comes in two forms: injections given at a doctor’s office (typically every few weeks) and sublingual tablets or drops placed under the tongue at home. Both work through the same immune mechanisms, gradually exposing you to increasing amounts of your trigger allergen.
Clinical studies show both approaches have similar effectiveness for respiratory allergies like pollen, dust mites, and pet dander. The injection route averages about 31 months of treatment, while the sublingual route averages around 19 months, though individual timelines vary widely. Treatment typically spans 3 to 5 years total for the best chance of lasting benefit. Stopping early often means symptoms return.
Newer Options for Food Allergies
For food allergies, two FDA-approved treatments now exist. One is an oral immunotherapy product for peanut allergy in patients ages 4 to 17, which gradually builds tolerance to small amounts of peanut protein through daily doses of peanut allergen powder. The other, approved in 2024, is an injectable medication (omalizumab) that works differently. Rather than introducing the allergen, it blocks the IgE antibodies responsible for allergic reactions, reducing the severity of accidental exposures to multiple foods at once.
In the clinical trial for omalizumab, 68% of participants who received the drug could eat the equivalent of about 2.5 peanuts without moderate to severe symptoms, compared to just 6% on placebo. For egg, 67% reached a similar threshold. For milk, 66%. For cashew, 42%. These treatments don’t cure allergies, but they raise the threshold for a dangerous reaction, providing a meaningful safety net against accidental exposure.
Can Living With a Pet Reduce Your Allergy?
The idea that you’ll “get used to” a pet by living with it has some scientific support, though the picture is complicated. High-dose, continuous exposure to cat allergen can trigger a modified immune response that is non-allergic in nature, essentially teaching the body to tolerate the protein rather than fight it. Some people who adopt a cat despite mild allergies do report that their symptoms fade over months.
The strongest evidence, however, is about prevention rather than treatment. Children who grow up with pets, especially those who have both cats and dogs, show lower rates of developing allergies in the first place. One large study found this protective effect extended into young adulthood and applied to both indoor and outdoor allergens, not just pet dander. The mechanism likely involves exposure to the microbial diversity that pets carry into the home, which helps calibrate the immune system during early development. This is consistent with the broader “hygiene hypothesis,” which holds that overly clean environments in childhood fail to provide the microbial challenges the immune system needs to mature properly.
For adults with established pet allergies, simply adopting a dog and powering through the sneezing is not a reliable strategy. Some will improve, but others will get worse, and there’s no way to predict which group you’ll fall into without trying.
Why DIY Exposure Is Risky
The logic of immunotherapy, that controlled exposure builds tolerance, sometimes leads people to try informal desensitization on their own. This is genuinely dangerous, particularly with food allergies. Allergic reactions are unpredictable. A dose that caused only mild hives one day can trigger anaphylaxis the next, depending on factors like exercise, alcohol consumption, illness, or how much sleep you got.
In a review of immunotherapy-related fatalities, dosing errors accounted for 21% of deaths, and several patients died because epinephrine wasn’t available or wasn’t administered correctly during a reaction. Clinical immunotherapy programs use precise, carefully escalated dosing under medical supervision for exactly this reason. Factors like uncontrolled asthma, cardiovascular conditions, and high degrees of allergen sensitization all increase the risk of a severe reaction during exposure. These are things a clinician screens for before starting treatment, and things you can’t account for on your own.
What Realistic Improvement Looks Like
For environmental allergies like pollen, dust, and pet dander, completing a full course of immunotherapy can reduce symptoms by a significant margin, and the benefit often persists for years after treatment ends. Many people don’t become completely symptom-free but find they can manage with fewer medications and less disruption to daily life. For food allergies, current treatments primarily raise the threshold for a reaction rather than eliminating the allergy, meaning you’re protected against accidental traces but not free to eat the food without limits.
Your age matters too. Adults are less likely than children to develop natural tolerance to food allergens, and respiratory allergies that begin in adulthood tend to be more persistent than those that start in childhood. That said, the severity of environmental allergies often fluctuates over a lifetime. Some people notice their hay fever improves in their 40s or 50s as immune function naturally becomes less reactive with age. Others find allergies that were mild in their 20s worsen in their 30s before plateauing. The immune system is not static, and neither are allergies.