Sun Poisoning or Photodermatitis

The sun

The sun produces invisible rays called ultraviolet-A (UVA) and ultraviolet-B (UVB) rays that can cause sunburn, suntan, and sun damage to the skin. Too much exposure to the sun can additionally cause sunburn, skin texture changes, and skin cancers. Cloudy days are dangerous too since UV radiation reaches the earth and can damage the skin.

Sun poisoning

Sun poisoning is a nonscientific term that refers to different sun-allergic reactions. It can be acute (sudden) or chronic (ongoing). Other terms used for the same condition include photodermatitis or polymorphus light eruptions (PLE).

Depending on the amount of sun exposure, reactions can vary from person to person. They most commonly occur after an episode of intense sun exposure, usually in the spring or early summer.

The symptoms may range from mild such as sunburn including red, itchy, hot patches and scaly skin to more severe forms such as vesicles or fragile bullae (fluid-filled, bubble-like under the skin), and skin turning dark and thick in chronic patients.

People with photosensitivity can also be affected by indoor fluorescent lighting, commercial tanning lamps and tanning beds.

Prevalence

The exact number of sufferers is not known as many patients do not seek medical attention. What is known is that women are more likely than men to suffer from photosensitivity. The condition can have a strong psychosocial impact on patients with women more likely than men to suffer from emotional distress.

 

Signs and Symptoms

    * redness, swelling and pain
    * itchy bumps or blisters
    * eczema-like lesions
    * dark patches on skin
    * chills and headaches
    * fever, nausea, vomiting
    * fatigue and dizziness
    * chronic sensitivity leads to thickening and scarring of the skin and increases risk of skin cancer

 

Causes

 
·   * Phototoxic - direct effects of the UV rays or taking chemicals or substances that make the skin more sensitive to UV light.
    * Photoallergic - effects that occur when a person exposed to sun is taking certain chemicals or medications that make their skin allergic to sunlight.
    * Certain diseases, including lupus and eczema, make skin sensitive to light as well as diabetes mellitus and thyroid disease
    * Genetic or metabolic factors (inherited diseases or conditions such as pellagra, caused by lack of niacin, vitamin B-3);
    * Herbs including St John’s Wort, Angelica seed or root, Arnica, Celery stems, Rue and Lime oil/peel

 

Direct toxic effects can be caused by:

    * Antibiotics, such as tetracycline and sulfonamides
    * Antifungals, such as griseofulvin
    * Coal tar derivatives and psoralens, used topically for psoriasis
    * Retinoids, such as tretinoin and medications containing retinoic acid, used for acne
    * Nonsteroidal anti-inflammatory drugs (NSAIDs)
    * Chemotherapy agents
    * Sulfonylureas, oral medications used for diabetes
    * Antimalarial drugs, such as quinine and other medications, used to treat malaria
    * Diuretics
    * Antidepressants, such as the tricyclics, used for depression
    * Antipsychotics, such as phenothiazines
    * Anti-anxiety medications, such as benzodiazepines

Allergic reactions can be caused by:

    * Fragrances
    * Sunscreens with PABA (para-amino benzoic acid which absorbs ultraviolet light and acts as a sun-blocker
    * Industrial cleaners that contain salicylanilide

Risk factors

    * Sunlight
    * Having fair to light skin, red or blond hair, green or blue eyes
    * Suffering from conditions such as lupus, porphyria, or polymorphous light eruptions, diabetes mellitus or thyroid disease
    * Underlying infection.
    * Previous episodes of sun poisoning.
    * Using birth control pills as well as the drugs possibly causing Direct toxic effects mentioned above
    * Using plants or topical cream containing psoralens
    * Using coal tar lotions
    * Perfumes with lemon oils and other products possibly causing allergic reactions.
    * Exposing to UV rays for over 30 minutes as well as exposure between11 a.m. and 2 p.m. when 50% of UV radiation is emitted.

 

How is diagnosis made?

Your doctor will perform a physical exam to examine your skin and take a detailed history of

         1. Symptoms
         2. Sun exposure
         3. Family Illnesses
         4. Medications used
         5. Topical creams used
         6. Jobs
         7. Habits - gardening, etc.

 
And order the following tests:

         1. Photo-testing by exposing you to UV light
         2. Photo-patch testing by applying the suspected agents or chemicals to patient's back for 48 hrs.  The patch is taken off and skin reaction is followed for one week.
         3. Skin biopsy in which a piece of skin tissue is sent to a pathologist to identify the underlying problem (if diseases are suspected)

 
Your doctor may even consult with a dermatologist.

Prevention

In order to prevent reactions to sun, make sure you

    * Limit skin exposure to sun, especially intense midday sun.
    * Avoid medications or topical creams that cause the problems.
    * Use PABA-free sunscreens that protect against UVA and have a sun protection factor (SPF) of 30 - 50.
    * Cover up with a long-sleeved shirt, long pants, and a wide-brimmed hat.
    * Avoid using tanning devices

Treatment Plan

For Sunburn
 

    * Apply cold water or ice compresses for sunburn as well as blisters and weepy eruptions
    * Drink lots of liquids, water would be the best.
    * Get aloe vera lotions that have soothing effects
    * Use tylenol or aspirin for pain or corticosteroid creams to ease the pain, redness, and itching.
    * Prednisone pills may be prescribed for severe reactions

 
Drug Therapies

Drug treatments are usually not necessary because the rash and other symptoms typically resolve on their own in seven to 10 days if preventive measures are applied.

However, if prevention steps aren't effective, a doctor may decide to prescribe a medication, such as a corticosteroid cream, to reduce the inflammation and to control eruptions. For extremely sun-sensitive patients, doctors may even prescribe azathioprine to suppress the immune system. Those individuals who cannot be treated with phototherapy may get hydroxychloroquine, thalidomide, beta-carotene, or nicotinamide. Thalidomide should be used with care and avoided by pregnant women and those trying to conceive, as the drug has been found to cause severe birth defects.

Treating photosensitivity with foods

The following foods may be helpful with treating photosensitivity:

    * Beta Carotene - found in carrots, as well as other carotenoids, are often used as a standard treatment although they have not been proven to be effective
    * Omega-3 fatty acids - found in fish and flax seed
    * Protein – for patients whose malnutrition may be a contributing factor.
    * Vitamin B3, Vitamin C, Vitamin D, and Vitamin E may make a photosensitive reaction less likely
    * Green tea has powerful antioxidant properties and may provide protection against reddening of the skin caused by UV light.
    * Antioxidants and flavonoids help protect skin against sun damage in healthy people by removing harmful, free radicals that occur as by-products of cells' use and generation of energy
    * Calendula is often used as a homeopathic remedy for sunburn
    * Aloe for external use
    * If pellagra is the cause, niacin would be the specific treatment

Prognosis/Possible Complications

Most photosensitivity reactions cause no permanent harm. However, if there is an underlying cause or in cases of severe exposure, the symptoms can get serious. Some photosensitivity reactions can continue for years.

Possible complications include

    * Ongoing photosensitivity, resulting in chronic photodermatitis
    * Hyperpigmentation or dark patches on the skin even after inflammation has ended
    * Premature aging of the skin
    * Squamous cell or basal cell skin cancer or melanoma

 

 Preventing complications or recurrence

People with a history of sun poisoning should stay out of the sun when possible. There should be no restrictions in every days’ activities as long as prolonged sun exposure is avoided. No special diet is necessary but drinking extra fluids to prevent dehydration is advised.


CALL the DOCTOR IF

New, unexplained symptoms develop as medications used in treatment may produce side effects.