It has been a long winter and the recent hot weather has got people excitedly spending more time outside in the sun, but for many instead of a lovely glowing tan, they may be left with an ugly red rash.
Rashes can actually be caused by sunlight itself in some people, however there are a number of things that can cause rashes which can be triggered by the sunlight including plants, medicines and fragrances, including sunscreens. If you do get a rash then you may need to figure out the exact reason for it and what you need to do to get rid of it!
Polymorphic Light Eruption
PLE is is easily mistaken for prickly heat. This rash is triggered by the sunlight and can show after as little as 20 minutes of exposure. It is common on skin that has been covered up for the winter months before suddenly being exposed to high levels of sunlight.
PLE will normally be stopped by covering up the skin and only exposing it more gradually to more sunlight over time. It will get worse if it is continually exposed to the sunlight after it first appears.
PLE is more common in women than it is in men and tends to be more prevelant in people with fairer skin.
What to do about it
The rash can be caused by both UVB and UVB radiation in sunlight. Use high factor broad spectrum sunscreen and cover up by wearing long sleeved loose fitting clothes.
Consult your GP if the rash gets worse.
Prickly heat
Prickly Heat is sometimes known as heat rash or miliaria, and is a red rash that gives a prickly sensation.It is caused by excessive sweat blocking the sweat glands.
Prickly heat looks like small bumps or blisters on red skin and commonly appear in the armpits, groin, waist, chest and insides of the upper arms and other places where sweat collects..
Young children and obese people are more prone to prickly heat, but anyone can get it.
What to do about it
Try to stay as cool as possible, perhaps by using products like Magicool Prickly Heat Spray. Wear loose cotton clothing and take regular cool showers. Calamine lotion may help to soothe the affected areas. Hydrocortisone creams may also provide some relief from itching, but shouldn’t be used on your face. Speak to your doctor or pharmacist about these.
Plants, Chemicals and the Sun
Contact with chemical compounds found in plants, grasses, sunscreens, insecticides and various toiletries, combined with sun exposure can also cause severe skin reactions.
Some of the main ones to watch out for are parsnips, celery, parsley, dill, fennel, limes and lemons, which contain chemicals called furocoumarins, naturally occurring phototoxins which, coupled with exposure to the sun, can trigger the rash.
Bergamot and musk oils in fragrances can have a similar effect. Similarly, chemicals used in sunscreens to absorb UV radiation can also cause this.
What to do about it
Try to work out what the cause is. Keep notes of the plants that you have been in contact with around the time that the rash appears and work it out. Try using sunscreens which act by blocking UV radiation or ones designed for sensitive skin instead.
Solar Urticaria
This is a rare condition where people develop hives within minutes of coming into contact with the sun. Resembling nettle rash, the itchy red patches of skin may also become swollen and soon disappear once the person has gone indoors out of the sunlight.
The rash often develops on areas of the skin usually shielded from the sun, such as the back. Other areas of the body which are constantly in the sun, such as the face or backs of the hands may be unaffected or only slightly so.
Solar urticaria is more common in women than men, can occur at any age, but most develop it before the age of 40. Although unclear, it is thought to be caused by an allergic reaction.
What to do about it
Exposing large areas of the body to sunlight – e.g. outdoor swimming – can lead to light headedness, headaches, nausea and vomiting.
People with solar urticaria are usually referred to a dermatology clinic where they will are advised about what lifestyle changes they should make.
These generally include wearing sun protective clothing, regularly using sunscreens and keeping out of the sun when it is most intense.
Anti-histamines may help reduce the rash and itching. Some patients may undergo ultraviolet desensitisation treatment.