Causes and Triggers of Eczema

How to Identify and Address the Most Common Types

Many people with eczema notice that their symptoms sometimes get worse. These disease flares are often triggered by certain environmental situations, which can be a little different for all people with eczema. By learning about your eczema triggers, you may be able to avoid them. This may help prevent flares of the disease.

A person putting cream on eczema on the back of their hand A person putting cream on eczema on the back of their hand

Irina Esau / Getty Images

What is Eczema?

Eczema is the common name for a skin condition formally known as atopic dermatitis. It is a chronic inflammatory skin disease that causes overly dry skin and itchy, red, and scaly sites on the body.

Some people with atopic dermatitis also have allergic rhinitis and asthma. People with atopic dermatitis tend to have an immune system that overreacts to certain substances, leading to symptoms.

It’s thought that the symptoms of atopic dermatitis are caused by a combination of environmental and genetic factors. Many people with eczema have a mutation in a gene that helps the skin maintain a healthy barrier with the external environment.

Because of this, the immune system may be exposed to substances in the outer environment that it wouldn’t normally encounter. This can cause some of the inflammatory problems of the disease.

What Are Disease Flares?

The immune problems causing atopic dermatitis aren’t completely understood. But it’s known that various environmental conditions (both internal and external), may worsen the skin’s inflammation. This can lead to something called a “disease flare,” in which symptoms get worse temporarily. For example, an area of skin that had been previously without symptoms might become red and itchy.

By avoiding triggers, one may be able to reduce skin inflammation and thus reduce symptoms.

However, it’s important to know that eczema is caused by a complex combination of factors: You are likely to still sometimes have symptoms even if you address all your potential triggers. However severe your disease is, knowing and reducing your triggers may help improve it.

Common Eczema Triggers

Different sorts of situations can trigger disease flares in someone with eczema. This might result in worsening symptoms, either very quickly or within a few days.

Some of these may apply to you, and but others may not. The disease shows up a little differently in everyone. Some people might not notice any specific triggers that make their disease worse.

There are many different potential categories of eczema triggers. Some of these are described below.

Skin Irritants and Contact Allergens

You may find that different substances found in both natural and artificial products seem to trigger your disease flares. These might include some of the following:

  • Certain types of clothing, like wool or polyester
  • Personal cleaning products (like shampoos, shower gels, bubble baths, baby wipes)
  • Other personal care products (like lotions)
  • Household cleaning products
  • Metals (most often nickel)
  • Perfume-based products
  • Antibacterial ointments
  • Certain disinfectants
  • Preservatives such as formaldehyde
  • Latex and adhesive bandages

In some cases, these substances serve as general skin irritants, which might worsen eczema symptoms broadly. In other cases, you might notice a skin rash directly where the aggravating substance touched. This might occur from a specific type of immune reaction in the body. You might hear these called “contact allergens” and the resulting rash called “allergic dermatitis” or “contact dermatitis.” 

Allergic dermatitis is very common in people with atopic dermatitis. Some people with atopic dermatitis sometimes get eczema from contact dermatitis as well. Both contact dermatitis and atopic dermatitis as forms of eczema.

Inhaled Allergens

Inhaling certain substances in the external environment can trigger allergies and worsen symptoms of atopic dermatitis. Some of the most common triggers of this type include:

  • Dust mites
  • Seasonal pollen from trees and grasses
  • Pet dander from cats or dogs
  • Mold
  • Cockroaches

Some people might also have their disease triggered by other inhaled substances, such as secondhand cigarette smoke.

Climate

Some people notice their eczema flares up during temperature extremes. For example, in the winter, there is less moisture in the air. This can increase skin dryness, which may increase eczema symptoms.

On the other hand, some people also notice that very hot temperature trigger their symptoms. Sweating itself may also worsen symptoms. Some people might even notice negative effects when they take long, hot showers or baths.

Specific Foods

Some people have reactions to specific foods that seem to worsen their eczema symptoms. Sometimes this is related to a true allergy to the food. Other times, people notice that eating the food seems to trigger their symptoms, even though they don't have what would be considered a true allergy.

Some of the most common food triggers that people describe are:

  • Cow’s milk
  • Eggs
  • Soy
  • Wheat
  • Peanuts
  • Other nuts
  • Fish
  • Shellfish

However, these are not the only foods that can potentially trigger symptoms. It’s also important to remember that different people may have different food sensitivities. You may have zero, one, or multiple food triggers. Food triggers for eczema may be more common in young children than in older children or adults.

Infection

Sometimes people with eczema can have their symptoms worsened by an infection. Conversely, a person with eczema might be more likely to get certain skin infections because of their disease. Some infections that might worsen skin symptoms include:

  • Staphylococcus aureus (staph)
  • Yeast infections
  • Molluscum virus
  • Herpes Simplex (the cause of fever blisters and cold sores)

Hormones

Some women notice that their disease tends to flare at certain times in their menstrual cycle. One study found that nearly half of all women with eczema notice worsened symptoms premenstrually.

Sex hormones such as estrogen and progesterone might be causing this, through their effects on the immune system. Some women also notice worsened symptoms during pregnancy.

Stress

Psychological stress may worsen eczema symptoms in some situations. You might be more likely to notice a flare during particularly stressful periods of your life. Factors such as poor or reduced sleep may also play a role.

Dry Skin

In one sense, dry skin might be better considered a symptom of eczema and than a trigger. People with eczema are prone to dry skin, even when they aren’t having any major symptoms.

However, keeping the skin hydrated with moisturizers and emollients is one of the most important things you can do to help prevent a disease flare. This will help keep more water inside your skin, which will leave it less prone to becoming painful, itchy, and red.

How To Identify Possible Triggers

Unfortunately, people with atopic dermatitis have somewhat different triggers, and identifying them can take a while. Some people can’t identify any particular triggers, even after they investigate.

Often, the easiest way to identify a trigger is by removing it and seeing if that helps reduce your symptoms. For example, you might do this by changing your laundry detergent or making changes in the clothes you wear. Learning about the most common types of triggers for eczema can give you some clues about what things you might try to remove.

It’s important to realize that your response to a trigger or removing a trigger might not occur right away. That can sometimes make it challenging to identify potential triggers.

Allergy Testing

Allergy testing may be able to help you identify triggers of eczema symptoms, such as specific foods or other substances. Unfortunately, the process of allergy testing is complex, and clinicians don’t all agree about the best tests to use or whether they are really helpful.

These tests are also difficult to interpret. Just because a test shows that you might be slightly sensitive to a substance, it doesn’t necessarily mean that it is triggering your symptoms. It may be helpful to work with a board-certified allergy specialist to get tested and make sense of your results.

Skin Prick Test: The skin prick test is one of the most common used to assess food allergies, which may act as eczema triggers. This involves placing a small amount of allergen on the skin and giving a small, non-painful scratch to the skin. A positive response shows an elevated red spot.

IgE Test: Another test that is sometimes used is a specific IgE test. This is a blood test used to check for certain antibodies in the blood. A specific type of test used to check IgE is known as radioallergosorbent testing (RAST).

Food Challenge Test: Sometimes these tests are followed up by food challenge tests. You might need this if one of your results showed that a food allergy might be partly triggering your eczema. In this scenario, the affected person avoids the suspected trigger for a period of time, then takes it under the supervision of a healthcare professional.

Reducing Exposure to Potential Triggers

There are a number of ways to reduce your exposure to potential triggers. They aren't difficult, but do take a bit of careful attention and planning.

Cleaning and Personal Care Products

Experiment with using different laundry detergents, cleaning products, etc., to see if that may help. Some people with eczema are sensitive to substances found in these products. Take a look at conventional products, but also so-called “natural” products because these can be disease triggers as well. Avoiding a suspected substance for a period of time can give you an idea of whether it might be triggering your symptoms.

Start by staying away from scented products. You might want to experiment with products labeled “hypoallergenic,” which may be less likely to trigger symptoms.

Generally, fewer ingredients are a good sign. Some people also experiment with homemade products, or simple baking soda and vinegar rinses.

In general, once you have identified a triggering substance, you’ll know to avoid it in the future.

Clothing

Since some people with eczema experience triggers from certain fabrics, you might want to look at your wardrobe. Some people with eczema find they do better with fabrics like silks and smooth cotton. But you may need to experiment to find what works for you.

Climate

Be aware of the potential for disease flaring from both overly dry and overly humid air.

In the summer:

  • Try to keep your skin clean, cool, and dry.
  • Wash away sweat, saltwater, or chlorinated water. Reapply moisturizer and sunblock (if needed)
  • Be aware that substances such as sunblock and mosquito repellents may contain irritants. You may need to experiment to find products that don’t irritate your skin. Hypoallergenic products are a good place to start.

In the winter:

  • Remember to use your emollients and moisturizers
  • Consider using an air humidifier to help keep the air moist.

Airborne Allergens

In some cases, you may be able to reduce your exposure to inhaled allergens, which might potentially reduce your symptoms. Some general things you could that might reduce your exposure include:

  • Using a high-efficiency particulate air (HEPA) filter
  • Using high-quality filters for your furnace and air conditioner and changing them regularly
  • Cleaning your home regularly (to help reduce exposure to dust mites)
  • Using dust-mite covers made for pillows and mattresses
  • Washing any pets at least weekly
  • Using insecticidal bait to reduce cockroach exposure
  • Reducing secondhand smoke exposure or other inhaled irritants

Some people also may be able to lessen their response to such allergens through immunotherapy or allergy shots.

Food Sensitivities

If you find that a certain food tends to trigger your eczema, it may be worth it to avoid it for a while. You may be able to reintroduce it at a later time without any problems. 

However, know that identifying such triggers can be very difficult, as symptoms might not show up for days, and a change in your symptoms might not be related to your diet. Also, be careful not to limit your diet too extremely.

Completely eliminating an item from your diet is unlikely to be helpful unless you already have substantial evidence that a specific food triggers your symptoms.

Making a food and symptom diary is a good way to track your symptoms over time. Then you can see if any patterns emerge.

General Self Care

By using general self-care, you can minimize the effects of your eczema triggers. For example:

  • See your healthcare provider right away if you have any signs of an active infection (like warm skin or pus).
  • Consistently use your preventative measures (such as emollients and lotions) and any prescription treatments, if needed, even when your disease isn’t actively triggered.
  • Take steps to manage the stress in your life (e.g., pursue enjoyable activities, take time to be social, meditate, seek counseling).

Considering Evidence

There is a lot that is still not understood about why some situations seem to trigger symptoms in some people with eczema. As you explore this topic, know that the research into eczema triggers is somewhat limited.

Part of the problem is that it can be difficult to design studies that assess how common these potential triggers are. It’s also hard to carefully assess the best interventions, partly because not everyone is sensitive to the same things. That’s why you might hear or read different information about this topic from different sources.

However, many people report that exposure to one of these triggers seems to flare their disease. In other words, there is what scientists call “anecdotal evidence.” For some of these triggers, we still don’t have thorough scientific evidence confirming this and explaining why. It is still often worth exploring whether these triggers might have an impact on you.

A Word from Verywell

It can be a long-term challenge to identify eczema triggers. It can be frustrating to make changes and not see improvements right way. However, with some persistence, identifying and managing your triggers may help you to minimize the disease’s impact on your life. 

Frequently Asked Questions

  • What causes eczema?

    Eczema is caused by a mix of genetics, environmental triggers, stress, and an overreacting immune system. You're more likely to have eczema if your family has a history of dermatitis or allergies.

  • Can eczema flare up in the summer?

    Yes, eczema can flare up in the summer—or during the winter. If your eczema gets worse during the summer, try keeping your skin clean, cool, and dry. If you experience eczema flare-ups during the winter, an air humidifier may help.

  • What aggravates eczema?

    Eczema can be triggered by a number of materials or substances. Some examples include wool or polyester clothing, personal cleaning products like shampoos or shower gels, household cleaners, metals (often nickel), perfumes, antibacterial ointments, and latex or adhesive bandages. It's important to pinpoint your triggers so you can avoid them.

  • Is eczema worse during pregnancy?

    In some cases, eczema can worsen during pregnancy. It's thought that hormones like estrogen and progesterone might be the cause. The severity of eczema is different for everybody, so there's no guarantee that pregnancy will result in worse symptoms.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Berke R, Singh A, Guralnick M. Atopic dermatitis: an overview. Am Fam Physician. 2012 Jul 1;86(1):35-42.

  3. National Eczema Association. Eczema causes and triggers.

  4. Sidbury R, Tom WL, Bergman JN, et al. Guidelines of care for the management of atopic dermatitis: Section 4. Prevention of disease flares and use of adjunctive therapies and approaches. J Am Acad Dermatol. 2014;71(6):1218-33. doi:10.1016/j.jaad.2014.08.038

  5. Langan SM, Williams HC. What causes worsening of eczema? A systematic review. Br J Dermatol. 2006;155(3):504-14.

  6. Raghunath RS, Venables ZC, Millington GW. The menstrual cycle and the skin. Clin Exp Dermatol. 2015;40(2):111-5. doi:10.1111/ced.12588

  7. National Eczema Foundation. Eczema and emotional wellness.

  8. Dhar S, Srinivas SM. Food allergy in atopic dermatitisIndian J Dermatol. 2016;61(6):645–648. doi:10.4103/0019-5154.193673

  9. Cleveland Clinic. Eczema. Last reviewed 10/28/2020.

Ruth Hickman Ruth Hickman

By Ruth Jessen Hickman, MD
Dr. Hickman is a freelance medical and health writer specializing in physician news and patient education.