Can Allergies Cause Loss of Appetite?

Dr. Menachof, MD, has specialized in conditions around the head, throat, ear, nose, neck and face for over 20 years, and was the first to bring sublingual allergy drops to Colorado in 2005. He has been recognized as a Fellow by multiple academies, named one of America’s Top Facial Plastic Surgeons continually since 2003 and is featured in multiple national publications.

Experiencing loss of appetite due to allergies? Learn more about why this happens and what it means to your health.

Seasonal allergies produce a slew of uncomfortable symptoms, including a runny nose, congestion, itchy eyes, sneezing, and fatigue. Because of these distressing symptoms, you might notice that food is the last thing on your mind. While loss of appetite has been linked to seasonal allergies or hay fever, it’s more commonly associated with the unpleasant side effects of medication and food allergies.

Regardless of whether your decreased appetite is related to airborne allergies or something you consumed, this frustrating symptom is both preventable and treatable. By discovering what you’re allergic to and understanding your body’s response, you can avoid contact with the allergen and treat common symptoms to help get your appetite back.

What Are Allergies?

An allergy is an abnormal reaction from your immune system to an ordinarily harmless substance (called an allergen). Allergens include things like pollen, dust mites, mold, animal dander, and certain foods. When an allergen enters the body of an allergic person, that person’s immune system views the allergen as an invader. White blood cells of the immune system produce IgE antibodies. These antibodies attach themselves to special cells called mast cells, causing a release of potent chemicals like histamine. These chemicals can cause many symptoms, including:

Allergies and loss of appetiteLoss of Appetite Caused by Allergies

Decreased appetite in relation to allergies is most often caused by a food allergy. When you ingest a food allergen, your intestines can swell and cause diarrhea, nausea, and vomiting. These symptoms diminish your desire to eat and worsen when you consume food.

Fatigue and loss of appetite are commonly associated. When you’re over-tired, you simply don’t feel as hungry. Because symptoms like congestion and itchy eyes and throat can affect your sleep, you may feel more tired throughout the day. This fatigue can have a major impact on your hunger. Additionally, allergies can cause increased mucus accumulation—ingesting a lot of nose drainage can cause nausea and decreased appetite.

Allergies can cause severe congestion in the nose. Chronic congestion can lead to an inability to smell normally. Because your sense of smell is so closely linked to your sense of taste, congestion can cause food to taste differently (or like nothing at all!), which has an effect on your appetite and interest in eating.

Loss of Appetite Caused by Pseudoephedrine

Drowsiness is often a side effect of pseudoephedrine, a decongestant medication that you can take to help alleviate allergy symptoms. Because of the link between tiredness and decreased appetite, pseudoephedrine is indirectly linked to loss of appetite. Additionally, when taken in higher doses, pseudoephedrine can cause central nervous system stimulation, increasing heart rate and blood pressure. This stimulation can cause appetite suppression in some people.

Treating Loss of Appetite

If you’re experiencing a decreased appetite due to food, medication or seasonal allergies, this symptom is highly preventable and treatable. Here’s how:

Allergy Test

The first step is to uncover what you’re allergic to with an accurate allergy test. An at-home allergy blood test can confirm specific allergens and the severity of your allergies.

Environmental Control

If your loss of appetite is due to food or medication allergies, the most effective way of treating this is to avoid the allergen altogether. This means changing your diet and avoiding certain foods.


If your allergies are related to airborne allergens, it’s more difficult to simply avoid the allergen. You can treat seasonal allergies with over-the-counter or prescription medications (like antihistamines and nasal steroid sprays) to help alleviate symptoms. For patients who are experiencing severe symptoms or who don’t want to take medications long-term, we suggest consulting an allergy specialist.

Sublingual Allergy Drops and Allergy Shots

You can also treat severe allergies with allergy shots or allergy drops that will slowly train your body not to react to allergic stimuli. While allergy shots have been the most effective way to treat allergy symptoms for many years, allergy drops are growing in popularity because of how easy and effective they are.

Get Help

At the Advanced ENT and Allergy Center, we’ve been treating allergy patients for over 20 years. We offer treatment plans specific to your unique allergies and symptoms. Let us determine the root of your symptoms and help you get your appetite back.

Schedule a free consultation today.

Denver’s Top
Allergy + Sinus Clinic

Our team has extensive, specialized training on allergy treatment and immunology from the American Academy of Otolaryngologic Allergy. Our allergy doctors were the first doctors in the state of Colorado to treat allergies with sublingual immunotherapy. We have a 20-year track record of helping patients find lasting relief.

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