Dr Phil Kieran: It can be hard to figure out exact cause of eczema flare-ups

One thing we commonly see at this time of year is a photo-irritation response. This can look like eczema and can be identified by appearing on an area where sunscreen, perfume or other skin products are applied and then exposed to the sun. I have seen this happen even with perfumes a patient has used extensively in the past without issue

Dr Phil Kieran: "When the skin dries out, it can start to stretch, which can make it itchy. Scratching this area (particularly while asleep) can cause damage to the skin, leading to further moisture loss and perpetuating the problem. This scratching also increases the risk of bacteria entering the skin and causing an infection."

My 14-year-old daughter had an eczema flare-up out of the blue, which we’re treating with over-the-counter medication. 

She had the condition as a child, but thankfully, she outgrew it. Is there any particular reason it reappeared, and what can she do to limit the likelihood of another flare-up?

Eczema, also known as atopic dermatitis, is a condition where the skin becomes irritated, then red, and can start to crack.

Many parents are familiar with this quite common condition which affects up to 20% of children in Ireland. 

Thankfully, as in your case, most children will grow out of it as they progress into adulthood. 

As the skin gets thicker and tougher, eczema usually becomes less of an issue (it affects approximately 3% of adults).

Eczema mostly occurs on what we call the flexural surfaces (inside the elbows, behind the knees, etc).

Anything that can cause allergic responses can also trigger eczema, as can anything that excessively dries out the skin. 

The most common of these triggers is soap, which can cause significant skin dryness by removing its natural oils. For patients with eczema, we typically recommend using a soap substitute for washing. This will help to keep the skin moisturised.

When the skin dries out, it can start to stretch, which can make it itchy. Scratching this area (particularly while asleep) can cause damage to the skin, leading to further moisture loss and perpetuating the problem. 

This scratching also increases the risk of bacteria entering the skin and causing an infection. Infected eczema appears redder, wetter, and is sore to the touch. This should be seen by your GP fairly quickly and is usually treated with antibiotics.

We also know that for some, hormonal changes can cause flares of eczema, particularly just before or in the early part of menstruation.

In your daughter’s particular case, I would be asking about any changes to detergent, shower products, or skin products. 

If she was previously moisturising regularly and then stopped, this can cause the eczema to reappear, having been controlled on the previous regimen.

If she has applied a new product, this may be a contact allergy causing an eczema-type skin response. 

Another thing we commonly see at this time of year is a photo-irritation response. This can look like eczema and can be identified by appearing on an area where sunscreen, perfume or other skin products are applied and then exposed to the sun. I have seen this happen even with perfumes a patient has used extensively in the past without issue.

Overall, if your daughter’s eczema has been well-controlled, it is pretty unlikely that this signals a return to more severe eczema. 

It is not unusual to experience occasional flares into adulthood, and this likely reflects that her skin is slightly more sensitive than that of someone whose skin has never had eczema. She should look into her skincare regimen and product usage to see if she can identify what may have triggered the flare-up, but often, we can’t figure out the exact cause.

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