Asthma and Allergies

Premier Health providers answer frequently asked questions on asthma and allergies.

How are Food and Skin Allergies Diagnosed?

Dr. Allen explains: How are Food and Skin Allergies Diagnosed?


If you think you might have skin or food allergies, your doctor can help you find out if you do, and what specific allergies you have and how to treat them.

Finding Out if You Have Food Allergies

Your doctor may use several steps to diagnose food allergies, such as:

  • Taking your history – Tell your doctor what reaction happens when you eat the food you think you’re allergic to; let your doctor know if you take any allergy medicines.
  • Diet diary – You may be asked to keep a detailed diary of all the foods you eat and whether or not you have a reaction. This diary may help and you and your doctor find a pattern.
  • Elimination diet – Once you’ve found out what you might be allergic to, you will remove those foods from your daily diet. If you still have a reaction without these foods, your doctor will help you look for another source.
  • Skin prick test – A needle with a tiny amount of food extract is injected just under your skin’s surface on your back or lower arm. If you are allergic, there will be redness and swelling at the site of the prick.
  • Blood test – A blood sample test may be used instead of a skin prick test; results are compared to your history to see if specific food allergies are likely.

Finding Out if You Have Skin Allergies

You may get a skin rash after coming in contact with an allergy-causing substance. Allergic skin reactions can be caused by heat, immune system disorders, medicines, infections and more, according to the American Academy of Allergy, Asthma and Immunology (AAAAI).

Some skin allergy conditions include:

  • Dermatitis (eczema) – If your skin comes in contact with an allergen, you can get dermatitis, which appears as red, bumpy, scaly, swollen or itchy skin.
  • Urticaria (hives) – Hives caused by an allergen can happen after coming in contact with a substance or a food that triggers your immune systems to release histamine; this causes small blood vessels to leak, which makes your skin swell.

If you’re not sure what allergen is causing your skin rash, your doctor may have you “backtrack” to see if you’ve been exposed to something new – like using a new soap or taking a new medicine.

For more information about how skin and food allergies are diagnosed, talk with your physician.

Learn More:

Source: Anessa Alappatt, MD, Fairborn Medical Center; J. Douglas Aldstadt, MD, Family Physicians of Englewood; Joseph Allen, MD, Family Medicine of Vandalia; Michael Chunn, MD, Michael A. Chunn, MD, Family Practice; Chandan Gupta, MD, Monroe Medical Center; Joseph Leithold, MD, Woodcroft Family Practice; Anne Reitz, MD, Centerville Family Medicine; Grenetta Ritenour, CNP, Jamestown Family Medicine; Melinda Ruff, MD, Centerville Family Medicine; Marcus Washington, MD, Premier Health Family Medicine; Mark Williams, MD, Beavercreek Family Medicine