Not everyone with asthma has eczema. But there’s a strong link between having eczema as a child and developing asthma later on in life. There’s no single explanation for this association. Early allergen exposure and genes may contribute.

Asthma and eczema are linked to inflammation. If you have one condition, research suggests you may be more likely than most people to have the other.

Here’s what researchers know about the link between asthma and eczema, along with tips to manage both conditions.

Eczema and asthma are linked to inflammation that’s often caused by a strong reaction to environmental allergens.

In fact, half of all people with moderate to severe eczema also have:

  • asthma
  • allergic rhinitis
  • food allergies

One study found that babies diagnosed with eczema in the first 2 years of life were three times more likely to develop asthma and rhinitis within the next 5 years than those who didn’t have infant eczema.

Other research has reached similar conclusions.

Eczema, or atopic dermatitis, is an inflammatory skin condition in which your immune system overreacts to an environmental trigger. The condition tends to be hereditary.

Inheriting a filaggrin gene mutation from your parents can lead to a “leaky” skin barrier, which reduces your skin’s ability to block allergens and allows moisture to escape.

This causes eczema symptoms like dry and irritated skin. Allergens, such as pollen, dander, and dust mites, contain enzymes that may also break down the skin’s barrier.

The wheezing, coughing, and chest tightness associated with asthma are often caused by a strong immune response to environmental allergens.

Inflammation causes the airways to swell and narrow, leading to breathing problems.

The exact causes of asthma are unknown and vary from person to person. Genes may play a role in the immune system’s strong reaction.

Allergic reactions occur when your immune system overreacts to certain benign substances. One unintended consequence of this response is increased inflammation in your body.

Your immune system releases antibodies and chemicals called histamines to combat these triggers. Histamine is responsible for classic allergy symptoms such as:

  • sneezing
  • runny nose
  • nasal congestion
  • itchy skin
  • hives and skin rashes
  • itchy, watery eyes

Allergies may cause several types of immune reactions in some people. It’s common for inhalant allergens to trigger allergic asthma and eczema.

Studies have increasingly linked eczema from inhalant allergens to a decrease in lung function. Examples of inhalant allergens include:

  • dust mites
  • pollen
  • mold
  • animal dander

Many other triggers besides allergens can cause asthma and eczema flare-ups. Some triggers can aggravate both asthma and eczema.

Possible eczema triggers include:

  • cold or dry air
  • stress
  • bacterial or viral skin infections
  • exposure to irritants found in detergents, soaps, fragrances, chemicals, and smoke
  • heat and humidity

The following may trigger asthma flare-ups:

  • cold or dry air
  • stress
  • upper respiratory infections
  • exposure to irritants like smoke, air pollution, or strong odors
  • heartburn
  • exercise

If you have both eczema and asthma, it’s important to ask an immunologist about allergy testing. A history of eczema could mean you’re more likely to develop allergic rhinitis and allergic asthma.

Even if you had allergy tests as a child, you can develop new allergies as an adult. Knowing your triggers can help minimize symptoms of eczema and asthma.

Once you know your triggers, it’s essential to reduce your daily contact with allergens as much as possible. You can start by:

  • using an air conditioner in your home
  • keeping windows closed
  • washing your bedding weekly in hot water
  • vacuuming carpets and rugs once a week
  • keeping pets out of your bedroom
  • taking showers immediately after you’ve been outdoors and before bedtime
  • maintaining a humidity below 40 to 50% in your home

If lifestyle changes and medications aren’t enough to manage your allergy-induced asthma and eczema, some treatments may help address both conditions. These include:

  • Immunotherapy: Regular allergy shots may help treat allergic asthma and eczema by introducing your immune system to tiny amounts of allergens. Your immune system builds up a tolerance until you experience fewer symptoms after 3 to 5 years of treatments.
  • Biologic medications: These newer anti-inflammatory medications are sometimes used to treat asthma and severe eczema.
  • Leukotriene modifiers (montelukast): This daily pill helps reduce allergy and asthma symptoms by controlling the chemicals your immune system releases when you come in contact with an allergen. It’s unclear whether it’s helpful in treating eczema.

Talk with an allergist or immunologist about which treatments might be right for you.

Not everyone who has asthma has eczema. And having eczema doesn’t always mean you’ll develop asthma.

A family history of allergies may increase your risk for both of these conditions. It’s possible to notice an increase in asthma and eczema flare-ups at the same time.

Lifestyle modifications and some treatments can help manage allergic asthma and eczema.

See your doctor if you’re noticing an increased number of flare-ups or if you’re having difficulty managing your symptoms.