Have you ever experienced red, itchy rashes on your skin? Does the appearance of these rashes increase with sun exposure? If so, you may be having a sun allergy.
Although such rashes are the most common presentation of a sun allergy, symptoms may be even more severe including hives and blisters. In some people, these symptoms may begin just minutes after exposure to the sun.
What causes a sun allergy?
- Immunological: It has been hypothesized that sun allergy is mainly the result of an immunogenic reaction. This means that during sun exposure, sun rays sometimes alter your skin in such a way that the white blood cells in your body recognize the sun-exposed skin as “foreign”.
Due to this, there is production of antibodies (mainly the IgE antibody) which attack your skin and cause rashes and itching to appear.
- Genetics– These allergies may be genetic, as having a relative with such allergies often puts you at a greater risk of having sun allergies. It is true that anyone can develop a sun allergy. However,researches have shown you may be more prone to developing sun allergies if you have lighter skin tones. This may be due to the fact that people with darker skin have more melanin, which is known to protect against sunlight.
- Skin Products: Sometimes, the substances you apply on your skin may be making your skin more sensitive to sunlight. This may include substances in lotions, perfumes or even in sunscreen.
The mechanism here is that the substance absorbs UV radiation and binds to the skin proteins- triggering an allergic reaction. In such cases, you may notice that you can normally go out in the sun without development of any itching and rashes. However, when you have put on a certain lotion, rashes begin to develop. Try and see if you have noticed with any of the products you use on your skin.
4. Drugs: You might also be aware that photosensitivity is a side effect of certain groups of drugs. These include certain antibiotics such as Doxycline, Tetracyclines; NSAIDs such as Ibuprofen, Piroxicam and Naproxen; Antihypertensives like Captopril, Methyldopa and Diltiazem; Antidepressants like Amitriptyline, Imipramine, Tazeodone; Hypoglycemics like Glipizide and Glyburide; diuretics such as Hydrochlorothiazide and Furosemide.
Types of Sun Allergies
Although there are various kinds of sun allergies, the four most common ones include:
- Polymorphous Light Eruption (PMLE):
PMLE is the most common type of sun allergy in the US, affecting about 10-15% of the population. Its symptoms mainly begin within a few hours of sun exposure.Its main symptoms are red, itchy rashes that are generally seen around the chest and arms. Caucasian women are the most affected population and symptoms often begin in the teenage years. It frequently occurs during spring time.
- Actinic Prurigo:
It is the inherited form of PMLE which displays more severe symptoms and in most cases, begins from childhood. The rash in this case is intensely itchy and often seen involving the face and the lips. This type of skin allergy is mostly seen affecting the American-Indian population.
- Solar urticaria:
This condition mainly affects young women. Although rare, this form of sun allergy is characterized by large, itchy red bumps called as hives. These hives are often only seen in the areas exposed to the sun.
- Photoallergic eruption:
This is caused as a result of the effects of sunlight on substances or chemicals worn on the skin in the form of lotions, etc. or substances ingested such as various drugs as mentioned before. In this type of photo allergic reaction, itchy or burning rash along with fluid filled blisters are common.
So lets see now, how do we get rid of sun allergies?
In order to get rid of sun allergies, the first thing to do would be to diagnose the type of sun allergy that you are suffering from. To do this, the following tests are often helpful:
- Photopatch testing: This test helps to identify whether your sun allergy is the result of any substance applied to your skin before you go out into the sun. In this test, the suspected substance (for example, a particular lotion) is applied to a small area of skin. Then, the area is illuminated with a measured dose of UV rays from a sun lamp. If only the area exposed to the UV rays is affected, then the allergy can be correlated with the substance. This helps to identify a photoallergic eruption.
- Ultraviolet (UV) Light Testing: This test helps to identify the type of sun allergy that you are having by testing your
skins reaction to various wavelengths of UV light.
- Skin samples and blood tests: These may sometimes be needed in order to rule out other systemic conditions that may be causing these allergies
Treatment of Sun Allergy
The following steps can be taken for treatment of sun allergies:
- The most obvious treatment is that you must stop your sun exposure!
- In most cases, sun allergies often resolve within 10-14 days, however, you must limit your sun exposure as much as possible.
- Cool compresses or cold water sprays can help relieve itchiness
- Drugs such as corticosteroids (eg-prednisolone), oral antihistamines and in some cases, anti- malarial drugs in the form of lotions and tablets can also be used.
- Anti-itch creams can should be used if needed
- Photo-therapy technique- it is a technique where the skin is exposed to UV light in small doses which helps the skin gradually build resistance (a phenomenon called ‘hardening’) which helps decrease the allergic symptoms
- Stop the usage of drugs and other substances that are increasing your sensitivity to light
- Application of moisturizers help alleviate the symptoms by retaining the skin moisture
- If none of the above seem to relieve your symptoms or if you are seeing persistent or unusual symptoms such as swellings, make sure you make an appointment with the dermatologist. There is no help like professional help!
As we all know, prevention is better than cure. Thus, use the following ways to prevent yourself from getting a sun allergy.
- Make sure you use a good sunscreen that is well suited to your skin
- Use umbrellas and long sleeved clothes to keep yourself shaded from the UV rays of the sun
- Use sunglasses to keep your eyes and face protected
- Be aware of the ingredients that are used in the skin products that you use
- Avoid going out in the sun during peak hours from 10 AM to 4 PM as the UV rays are most harmful at these hours