The lichen planus is a skin rash which is triggered by the immune system . It is not known why the immune system response occurs. There can be several contributing factors and each case is different. The most common causes are genetics, stress, allergens and viral infections. There are some cases when the lichen planus is happening along with autoimmune disorders.
This may be uncomfortable, but in most cases, the lichen planus is not a serious condition and it is not contagious. There are some rare cases when some rare variations of this condition that can be serious and painful. The lichen planus can be treated with topical and oral medications to reduce the symptoms or to use drugs which can suppress the immune system.
When it is on the skin, then it usually appears as purplish, itchy and flat bumps which develop over several weeks. When it happens in the vagina, mouth and other areas covered by a mucous membrane, then the lichen planus is forming lacy white patches and sometimes, they have painful sores. In most cases, people can manage typical and mild cases of this at home, without medical care.
Here are some of the most common symptoms of lichen planus :
Thin white lines over the rash
Blisters, which burst and become scabby
You can have lacy – white lesions in the mouth, which may be painful or cause a burning sensation
Painful sores in the mouth or vagina
Itching at the site of the rash
Nail damage or loss
Lesions that develop and spread over the body over the course of several weeks or a few months
Change in the scalp colour
You can have a purplish – coloured lesions or bumps with flat tops on your skin or genitals
It is known that the most common type of lichen planus affects the skin. In a period of several weeks, lesions appear and spread. Usually, this condition clears up in a period of 6 – 16 months. There are less common cases when the lichen planus can happen in areas besides the skin or genitals. These may include the scalp, nails and the mucous membranes.
It is noticed that variations of this condition are more common in Latin America, Africa, Asia and the Middle East . You should see a doctor if you have tiny bumps or a rash-like condition that appears on your skin for no apparent reason, such as a known allergic reaction or contact with poison ivy. Also, you should talk with your doctor if you experience any signs or symptoms associated with lichen planus of the nails, scalp, genitals or mouth.
It happens when the body attacks your skin or mucous membrane cells by mistake and doctors are not sure why this happens. The lichen planus can happen in any single person at any age, but there are some factors which can make a person more prone to developing this condition.
The skin form of lichen planus happens in both men and women equally, but women have two times more chances to get the oral form. It is very rare for the lichen planus to happen in children and older adults. It is most common in middle-aged people . It is very important to get a prompt and accurate diagnosis because there are many skin and mucosal conditions which can cause lesions and discomfort.
Some of the most common risk factors for lichen planus include:
Being exposed to certain chemicals that act as allergens (such as, certain kinds of dyes; diuretics; iodide compounds; gold; arsenic and antibiotics) 
Having a viral disease, like hepatitis C 
Have a family member who has had lichen planus 
If you develop the lichen planus on your vagina or vulva, then it can difficult for this condition to be treated. This could lead to discomfort, scarring and pain during sex. Also, if you develop lichen planus, then it can increase your risk of squamous cell carcinoma.
The increase in the risk is small, but you should see your doctor for the routine skin cancer examinations. The lichen planus can be uncomfortable, but it is not a dangerous condition. With time and a combination of prescribed and home treatments, the rash will clear up.
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