|For some people, exposure to the sun will result in a rash.|
Most of us enjoy the sun, but some people's skin can be very sensitive to the sun in spring and summer, especially those with pale skin and red hair. For them, exposure to sunlight results in a rash which may recur throughout the summer.
A sun rash is seen as small, reddish blisters or small or large spots in areas that have been exposed to sunlight. Some areas, for example, the face, can be spared. This rash usually appears after minutes' or hours' exposure to the sun and can be extremely itchy.
It is commonly seen in children and young women and tends to be recurrent. Those who suffer from it get relief only during the winter. The condition usually disappears as they get older and reach their 40s or 50s.
Over exposure to the sun may lead to premature ageing of the skin and an increased risk of skin cancer.
Use common sense and avoid the direct sunlight when it is most intense around midday and early afternoon. It is important to keep in the shade and to wear appropriate clothing, eg sun hats, sunglasses with proper UV protection and clothing material that doesn’t allow the sun through easily.
It is very annoying to return from a holiday with a skin rash instead of a nice tan. Unfortunately, we do not know why some people are so sensitive to sunlight. However, there is one preventive treatment that can be offered.
The only remedy is to use a sunscreen with a high sun protection factor (SPF). The SPF indicates how effectively the cream protects you from the more harmful light ultraviolet B wavelength (UBV) sunlight. A sunscreen with a SPF of 10 should in theory allow the individual using it, to remain in sunlight 10 times longer without burning.
Although ultraviolet B wavelengths (290-320nm) are mainly the cause of skin damage from the sun, ultraviolet A (UVA) wavelengths (320-400nm) can also cause damage and the majority of sunscreens available to purchase have blocking agents that act against both.
People who suffer from sun rash or sun spots should start with a cream with an SPF of 15 to 25 and higher (eg Uvistat Ultrablock).
You may be able to use a cream with a lower SPF after one or two weeks when the skin has had time to get used to sunlight.
For watersports use water-resistant emulsions.
Photoallergic dermatitis can be caused by the action of sunlight on skin exposed to certain chemicals. Some substances such as perfume or soap can make the skin extra sensitive to the sun.
Photoallergic dermatitis can be prevented by avoiding contact with the substances that cause it. You may discuss this with your doctor before going on a holiday.
Drug-induced photosensitivity occurs when an individual develops a rash on exposure to the sun while taking a certain drug. Medicines that may cause this include: thiazide diuretics, tetracycline antibiotics, NSAIDs (painkillers), etc. Your doctor or pharmacist will be able to provide advice about medicines that are likely to cause this reaction.
Based on a text by Dr Per Grinsted
Last updated 06.10.2008