Ask the Allergist: Expert Answers on Allergies & Asthma

Welcome to our new Ask the Allergist series, where we connect you with expert medical advice. We are partnering with board-certified allergists to provide authoritative answers to your most pressing questions about allergies, asthma, and related conditions.

For our inaugural session, we are honored to feature Dr. Frank Lichtenberger, MD, PhD. Dr. Lichtenberger addresses three of the most common questions we receive, helping to clarify the complexities of allergic reactions and their connections to other health issues.

How to Tell the Difference Between a Cold and Allergies

Distinguishing between a common cold and seasonal allergies can be challenging, even for healthcare professionals, due to overlapping symptoms. Both conditions can cause:

• Upper and lower respiratory tract inflammation
• Irritated, watery eyes
• Coughing and fatigue
• Nasal congestion

However, key differences exist. Colds, caused by viruses, often lead to more systemic symptoms like body aches, nausea, and stomach upset. Allergies, on the other hand, typically involve more pronounced itching and produce thin, watery nasal and eye secretions. Antihistamines are common in cold medicines precisely because they effectively reduce the nasal inflammation shared by both conditions.

The Link Between Allergies and Asthma

Allergies and asthma are frequently connected through a condition known as Atopy. Atopy describes a genetic predisposition where the immune system overreacts to common allergens.

This shared immune response means the same processes that cause a stuffy nose from pollen can also trigger asthma symptoms in the lungs or lead to itchy, scaly skin (eczema). Notably, children diagnosed with food allergies or eczema have a significantly higher likelihood of developing asthma later in life, highlighting the importance of monitoring and managing these interconnected conditions.

Are Environmental and Food Allergies Related?

Yes, environmental and food allergies can be directly related through a phenomenon called cross-reactivity. This occurs when proteins in certain foods are structurally similar to proteins found in environmental allergens like pollen.

Think of the immune system recognizing allergens by a specific molecular “code.” If the code for birch pollen (e.g., “BRCH”) is very similar to the code for an apple protein (e.g., “BCRH”), the immune system may react to both. This is often the cause of Oral Allergy Syndrome, where someone might experience an itchy mouth after eating raw fruits or vegetables, not due to a true food allergy, but because of their existing pollen allergy.

Other common cross-reactivities include:

• Dust mites and shellfish
• Ragweed pollen and melons (e.g., cantaloupe, watermelon)
• Grass pollen and tomatoes or potatoes

Submit Your Question to Our Allergist

Do you have a question about allergies, asthma, or management strategies? Our Ask the Allergist feature is here to help. Submit your questions, and our medical experts may select yours for a detailed answer in a future post.

Author: Kevin Gilmore