Medical questions & health advice by board certified doctors
"What causes big white patches?"
I have big white patches on my shoulders and back. I didn't think they were so prominent until I got more tanned, and now they really stand out. I'm a 31 year old woman and they're making me very self-conscious. What can I do?
There are many causes of skin hypopigmentation (light spots of skin surrounded by darkened areas). If this is the first time you have noticed it, then you should be evaluated by a dermatologist. A common skin infection that causes white patches to form is a fungal infection known as tinea versicolor. This fungus can infect the skin without causing any symptoms. It may not even show up until you try to get a tan and realize some of the areas of your skin won't get any darker. The areas may also appear red or pink. Another possibility is a disease called vitiligo. This is where the body's immune system attacks the cells which are responsible for skin pigmentation. This results in patches that appear whiter than the outside skin and can progress until all the skin is that color. I suggest that you schedule an appointment with a dermatologist. He or she can perform a close physical exam of your skin spots and determine which possibility it is. If you do have a skin fungal infection (tinea versicolor), then your doctor may try you on a medicated cream, or anti-fungal oral medication. If a skin infection is not suspected, you may require a biopsy of the area or some blood tests for a diagnosis.