Photodermatitis Rash From Sun: Healing Skin Symptoms
Medically reviewed by Brendan Camp, MD
Photodermatitis is a condition that causes a rash on the skin. It occurs when the skin is exposed to both an irritant and ultraviolet (UV) light. It is a type of photosensitivity but uniquely different from sunburns.
This article will discuss all the aspects of photodermatitis, including symptoms, treatment, and prevention.
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Photodermatitis vs. Photosensitivity
Photosensitivity is an umbrella term that is used to describe several symptoms and conditions caused or triggered by sunlight.
Photodermatitis is a rash caused by sunlight.
People with photosensitivity can present with many different symptoms or conditions when they are exposed to sunlight. One of these conditions is photodermatitis.
Learn More: What Does a Sun Rash Look Like?
What Causes Photodermatitis?
Photodermatitis is caused when someone has an underlying condition, takes a particular medication, or applies a triggering substance to their skin and then is exposed to sunlight. The combination of the sun and the trigger causes the photodermatitis rash.
Medications or substances that may cause photodermatitis include:
Antibiotics
Antifungals
Retinoids
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Sulfonylureas
Chemotherapy
Diuretics
Antidepressants
Examples of underlying conditions that may cause photodermatitis are:
Photodermatitis vs. Sunburn
Photodermatitis can look like a serious sunburn but it occurs under much less sunlight exposure than a typical sunburn. It also needs another trigger along with sunlight to cause the rash. A sunburn will happen with prolonged sunlight exposure and does not need additional triggers.
Symptoms: How Does Photodermatitis Affect Skin?
Photodermatitis only appears on areas of the skin that are exposed to the sun. It is often found on the hands, face, neck, forearms, and feet. The symptom duration is difficult to predict. In some people, it is chronic, whereas in others, it goes away after the triggers are removed.
The symptoms of photodermatitis include:
Raised red scaly skin patches
Itchy bumps or blisters
Pain
There can also be skin thickening and scarring if the condition becomes a long-term issue.
Diagnosing Photodermatitis
When someone comes to their healthcare provider for a photodermatitis diagnosis, the workup will include a physical exam to assess the skin and rash. The healthcare provider may ask about previous sun exposure, current medications, and family history.
If the healthcare provider suspects photodermatitis, they may perform photo tests. This is where a small area of the skin is intentionally exposed to UV radiation. Another test is photopatch testing, in which two sets of an allergen are placed on the skin, and one is exposed to UV radiation.
Treatment: Tending to Skin With a Photodermatitis Rash
Photodermatitis treatment consists of topical creams and medications, oral medications, and sun avoidance. Some of these treatments can be done at home, whereas others need a healthcare provider.
At Home
In some cases, photodermatitis can be managed at home.
The rash is similar to eczema and may be treated using a fragrance-free moisturizer and over-the-counter topical steroids. Other at-home treatments include stopping any photosensitizing medications and avoiding contact with known allergens.
Under Provider Supervision
A healthcare provider can offer treatments to lessen photodermatitis and reduce its incidence.
In people who are very sensitive to the sun, medications like azathioprine can be used to suppress the immune system along with oral corticosteroids.
A healthcare provider may use phototherapy, a controlled light exposure, to desensitize the skin. If phototherapy is not an option, then the healthcare provider may prescribe thalidomide, hydroxychloroquine, nicotinamide, or beta-carotene.
Sun Protection With Photodermatitis
One of the best ways to prevent photodermatitis is to stay out of the sunlight or to protect the skin when outside.
If staying out of the sun is not an option, limit midday sun exposure when sunlight is most intense. Consider wearing clothing that offers UPF (ultraviolet protection factor) protection.
Apply sunscreen that has an SPF (sun protection factor) of 30 or more, and do not use products that cause sun sensitivity. Examples of products that increase sun sensitivity include retinoids, vitamin C, salicylic acid, and benzoyl peroxide.
When to See a Healthcare Provider
It's important to see a healthcare provider to get a photodermatitis diagnosis. Several conditions look similar, however, treatment will be different. Knowing the diagnosis and underlying cause will guide healthcare providers to specific treatments.
When someone has photodermatitis due to an underlying condition—or when it is severe—they should see their healthcare provider regularly. Photodermatitis can cause complications like hyperpigmentation (darker patches of skin), premature aging, and skin cancer.
Summary
Photodermatitis is a skin condition caused by an allergen or skin irritant, that when exposed to UV light causes a rash. People who have photodermatitis need to avoid sunlight, wear clothes that cover their skin, and use sunscreen. A healthcare provider can prescribe medications to help alleviate the symptoms and help minimize future rashes.
Read the original article on Verywell Health.
