Skip to main content

Ask a Doctor: What You Need to Know About Allergies

Judyann Krenning , MD sees patients at Phelps Health
Judyann Krenning, MD, is an otolaryngologist (ENT) with the Phelps Health Medical Group.

Published on September 5, 2019

What is an allergy?

"An allergy is the body’s reaction to an allergen it doesn’t like," said Judyann Krenning, MD, an otolaryngologist (a doctor who specializes in ear, nose and throat, or ENT, care) with the Phelps Health Medical Group. Allergies can be mild or severe and immediate or delayed. The most common allergies are found either to be environmental and/or food.

What are common causes of allergies?

Mold, pollen and pets, such as cats and dogs, are some of the main causes of environmental allergies, while dairy, wheat and eggs are common causes of food allergies.

What happens during an allergic reaction?

What happens when a person has an allergic reaction varies. "Usually, they suffer itchy and watery eyes, sneezing or drainage in the throat with environmental allergies," Dr. Krenning said. People with food allergies may experience eczema or a rash, abdominal pain and sometimes, ear infections.

How do I know if I have allergies or a cold?

"Sometimes, it’s difficult to tell the difference," Dr. Krenning said. "With a cold, you usually have an increase in your body temperature and the mucus is usually thick or cloudy and sometimes yellow. With allergies, the mucus is almost always clear." Additionally, colds usually last several days or up to two weeks, whereas allergies last much longer.

Can allergies be cured?

The answer is sometimes, according to Dr. Krenning. With allergy shots, a patient may become desensitized to certain allergens. "If you have taken allergy shots for three to five years, and you are retested after that, you may find out you no longer react to certain allergens, like cedar," she said.

How can I control my allergies?

If you cannot avoid the allergen, the next best step is medical management. That may include taking antihistamines, using nasal sprays or getting allergy shots. On rare occasions, steroids can be used.

Tell me about allergy shots.

Allergy shots can be given at your doctor’s office. After the first few visits, some patients may be able to have a spouse or parent give them allergy shots at home. Dr. Krenning said drops or tablets can be placed under the tongue to help with allergies.

What does hypoallergenic mean?

Hypoallergenic refers to products that have less or no allergens in them. Examples of hypoallergenic products may include deodorant or laundry detergent.

For more information about allergies, visit or call the Phelps Health Medical Group at 600 Blues Lake Parkway in Rolla at (573) 364-5719.

Found in: Allergy Care ENT Health