Food Allergy: Causes, Symptoms, and Treatment
Medically reviewed by Sumiran Racherla, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Food Allergy?
An allergist, a doctor who diagnoses and treats allergies, usually treats food allergy. Anyone who has had an allergic reaction to a food should be seen by an allergist. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is food allergy?
A food allergy is an abnormal immune system reaction to certain foods. Your immune system normally fights germs. With a food allergy, it wrongly treats some foods as harmful. The reaction is usually mild, but it can be serious or even life-threatening. In the United States, food allergy affects about 8 percent of children and nearly 11 percent of adults.
A food intolerance is different. It also causes symptoms after you eat a food. But they are usually digestive, such as bloating and gas, and it is not an immune system reaction.
Symptoms
Symptoms usually start within a few minutes to two hours after you eat the food. Symptoms can include:
- Hives, flushed skin, or a rash.
- A tingling or itchy feeling in the mouth.
- Swelling of the face, tongue, or lips.
- Vomiting, diarrhea, or stomach cramps.
- Coughing, wheezing, or trouble breathing.
A food allergy can cause anaphylaxis. This is a life-threatening reaction that affects the whole body. It can narrow the airways in the lungs and cause severe trouble breathing from throat swelling. It can also cause a severe drop in blood pressure, shock, and loss of consciousness. Wheezing or trouble breathing after eating a food needs emergency care, as explained under When to see a doctor.
Causes and who gets it
In a person with a food allergy, the immune system is oversensitive. When it sees an allergen, it releases chemicals such as histamines that cause the symptoms. An allergen is a substance that triggers an allergy. Most food allergies are caused by cow's milk, chicken eggs, shellfish, fish, peanuts, sesame, soy, tree nuts, and wheat.
Both children and adults can have food allergies. Some children outgrow them, and some people develop them as adults. You are more likely to have a food allergy if you have eczema, asthma, or other allergies. A family member with allergies, asthma, or eczema also raises the chance.
How doctors diagnose it
A provider will ask about your symptoms. You will also be asked about your family history. The provider will likely do a physical exam. Tests can include skin tests, blood tests, or a food challenge. An oral food challenge is the most accurate test. In a challenge, you eat a small amount of the suspected food with a doctor watching. The test may cause a severe allergic reaction. Never try to cause a reaction or reintroduce a food on your own.
Treatment
Avoiding the food is the most effective treatment. When you eat away from home, ask detailed questions about the food. When you buy food, read package ingredients carefully. If you have symptoms in only one area of your body, such as one hive on your chin, you may not need any treatment. The symptoms will likely go away in a brief time. Antihistamines and soothing skin creams may relieve discomfort.
If you have a serious reaction that affects the whole body, learn how to use injectable or nose-spray epinephrine. Epinephrine is the medicine that treats anaphylaxis. You should have two epinephrine devices with you at all times. After using epinephrine, go to the nearest emergency room right away, preferably by ambulance.
In desensitization, you eat a small amount of the food each day, and this must be done under an allergist's guidance. Omalizumab (Xolair) is a shot every 2 or 4 weeks that can lower your sensitivity to foods. Allergy shots and probiotics are not proven to help. It is a good idea to wear a medical alert bracelet that says what your allergy is.
When to see a doctor
Call 911 or the local emergency number if you have a serious reaction that affects the whole body after eating any food. This is true above all for wheezing or trouble breathing. If your provider prescribed epinephrine, use it as soon as possible, even before calling 911. See an allergist if you suspect that you or your child has a food allergy.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either can evaluate you, follow up, and refer you to an allergist.
Common questions
Can you outgrow a food allergy?
Yes, some children outgrow food allergies. Allergies to peanuts, tree nuts, and shellfish tend to last a lifetime.
What is the difference between a food allergy and a food intolerance?
A food allergy is an immune system reaction, while a food intolerance is not.
Can you develop a food allergy as an adult?
Yes, people can develop food allergies as adults.
What should I do if I have a reaction after eating a food?
If the reaction is serious or affects the whole body, call 911 or the local emergency number. If your provider prescribed epinephrine, use it as soon as possible, even before calling 911.
Can food allergy be prevented in babies?
Giving babies peanut-containing foods may help prevent peanut allergy. There is also evidence that introducing eggs by 12 months of age can prevent egg allergy.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
