Allergies and Asthma: Is There a Connection?

Both allergies and asthma can cause respiratory symptoms, such as coughing and airway congestion. However, there are also symptoms unique to each disease. Allergies may cause:

• watery and itchy eyes
• sneezing
• runny nose
• scratchy throat
• rashes and hives

Asthma usually does not cause those symptoms. Instead, people with asthma more often experience:

• chest tightness
• wheezing
• breathlessness
• coughing at night or in the early morning

Allergy-induced asthma

Many people experience one condition without the other, but allergies can either worsen asthma or trigger it. When these conditions are so closely related, it’s known as allergy-induced, or allergic, asthma. It is the most common type of asthma diagnosed in the United States. It affects 60 percent of people with asthma.

Many of the same substances that trigger allergies can also affect people with asthma. Pollen, spores, dust mites, and pet dander are examples of common allergens. When people with allergies come into contact with allergens, their immune systems attack the allergens the same way they would a bacteria or a virus. This often leads to watery eyes, runny nose, and coughing. It can also cause a flare-up of asthma symptoms. Therefore, it can be helpful for people with asthma to closely watch the pollen count, limit time spent outside on dry and windy days, and be mindful of other allergens that may induce an asthmatic reaction.

Family history affects a person’s chances of developing allergies or asthma. If one or both parents have allergies, it’s much more likely that their children will have allergies. Having allergies such as hay fever increases your risk of developing asthma.

Most treatments target either asthma or allergies. Some methods specifically treat symptoms related to allergic asthma.

• Montelukast (Singulair) is a medication primarily prescribed for asthma that can help with both allergy and asthma symptoms. It’s taken as a daily pill and helps to control your body’s immune reaction.
• Allergy shots work by introducing small amounts of the allergen into your body. This allows your immune system to build up tolerance. This approach is also called immunotherapy. It usually requires a series of regular injections over several years. The optimal number of years has not been determined, but most people receive injections for at least three years.
• Anti-immunoglobulin E (IgE) immunotherapy targets the chemical signals that cause the allergic reaction in the first place. It’s usually only recommended for people with moderate to severe persistent asthma, for whom standard therapy has not worked. An example of anti-IgE therapy is omalizumab (Xolair).

It’s important to note that while there is a strong connection between allergies and asthma, there are many other possible asthma triggers to be aware of. Some of the most common nonallergenic triggers are cold air, exercise, and other respiratory infections. Many people with asthma have more than one trigger. It’s good to be aware of different triggers when you’re trying to manage your symptoms. The best defense against allergies and asthma is to pay attention to your own triggers, as they can change over time.

By being informed, consulting with a physician, and taking steps to limit exposure, even people with both asthma and allergies can effectively manage both conditions.