0
We're unable to sign you in at this time. Please try again in a few minutes.
Retry
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
Retry
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
JAMA Patient Page |

Food Allergies FREE

Huan J. Chang, MD, MPH, Writer; Alison E. Burke, MA, Illustrator; Richard M. Glass, MD, Editor
JAMA. 2010;303(18):1876. doi:10.1001/jama.303.18.1876.
Text Size: A A A
Published online

A food allergy is an adverse immune response to a food. Your immune system makes antibodies to protect you from germs and disease, but it may also sometimes make antibodies to certain food proteins. Some of these antibodies (called IgE) are known to be associated with allergic reactions. When that happens, your immune system treats the food as if it were a harmful substance, resulting in an allergic reaction. The proportion of people with food allergies is not known with precision because of differing definitions, but it is between 2% and 10% and is more common in children than adults. The May 12, 2010, issue of JAMA includes a review article about food allergies.

TRIGGERING A REACTION

Food allergies can cause serious illness or death. The most common food allergies are to proteins in cow's milk, eggs, peanuts, wheat, soy, fish, shellfish, and tree nuts. In people with food allergies, even a tiny amount of the food can trigger an immune response. Peanuts and tree nuts are the leading causes of severe food allergic reactions. In the immune response, IgE antibodies cause mast cells (type of immune system cell) to release chemicals into the bloodstream. Histamine, one of these chemicals, causes many of the symptoms listed below. Anaphylaxis occurs when several of these symptoms occur simultaneously and may include decreased blood pressure, narrowed airways in the lungs, and tongue swelling.

SYMPTOMS

Allergic reactions to food can be mild to severe. They usually occur within a few minutes of eating a food, though they rarely appear a few hours after ingestion. Symptoms can include runny nose, itchy skin, rash or hives, tingling in tongue or lips, tightness in throat, hoarse voice, wheezing, cough, nausea, vomiting, stomach pain, or diarrhea.

FOOD ALLERGY VS FOOD INTOLERANCE

Food intolerance is often confused with food allergy. Food intolerance is a less serious condition that does not involve the immune system. It is more common than food allergy and occurs when the digestive system is unable to properly break down food. Lactose intolerance after eating dairy foods is the most common form of food intolerance. Symptoms may include diarrhea, stomach pain, and vomiting, but not hives, airway swelling, or anaphylaxis.

TREATMENT AND PROGNOSIS

Food allergies, like other allergic conditions, are believed to have a strong genetic component but may develop at any age. The clinical history, use of skin prick tests, and blood tests for antibodies to particular foods all have a role in making a diagnosis. In some cases, oral food challenges are necessary, and these should be done by a qualified allergist (a doctor with specialized training in diagnosing and treating allergies). Management typically includes avoidance of the specific foods identified by clinical evaluation and allergy testing and development of an emergency treatment plan in the event of accidental exposure or ingestion. The plan should include what to do, whom to tell, and which medications to take. Antihistamines (medications that block histamine effects) are not a substitute for an epinephrine autoinjector, which can be self-administered by the patient for a severe allergic reaction. After using epinephrine, you should go to a hospital for evaluation and observation. Read food labels carefully and ask about ingredients before eating food prepared by other persons or restaurants. Some people wear medical alert jewelry. Many children outgrow allergies to milk and eggs, but severe allergies to foods like peanuts, some fish, and shrimp can last a lifetime.

FOR MORE INFORMATION

INFORM YOURSELF

To find this and previous JAMA Patient Pages, go to the Patient Page link on JAMA's Web site at http://www.jama.com. Many are available in English and Spanish.

Sources: National Institute of Allergy and Infectious Diseases; American Academy of Allergy, Asthma, and Immunology

The JAMA Patient Page is a public service of JAMA. The information and recommendations appearing on this page are appropriate in most instances, but they are not a substitute for medical diagnosis. For specific information concerning your personal medical condition, JAMA suggests that you consult your physician. This page may be photocopied noncommercially by physicians and other health care professionals to share with patients. To purchase bulk reprints, call 312/464-0776.

TOPIC: ALLERGIES

Figures

Tables

References

Letters

CME
Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.

Multimedia

Spanish Patient Pages
Supplemental Content

* * SCHEDULED MAINTENANCE * *

Our websites may be periodically unavailable between midnight and 04:00 ET Thursday, July 10th, for regularly scheduled maintenance.

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Articles Related By Topic
Related Collections
PubMed Articles