Most often, a rash on the knees itches due to a banal food allergy or an allergic reaction to drugs, cosmetics. Less commonly, the body reacts to tissue or natural dust. In this condition, areas of red swollen rash appear on the skin that will peel off. In severe cases of allergic dermatitis, not only the usual urticaria, but even weeping eczema develops . The most important thing in this situation is to eliminate the cause of the allergy. Antihistamines and ointments (such as Fenkarol or Fenistil) will also help.
There are many reasons - one symptom
In the winter season, especially against the background of hypothermia, general dry skin and hypovitaminosis, eczema-like rashes on the hands and feet often develop, accompanied by itching. An itchy rash on the legs may well be associated with a reaction to depilation, but it is also a striking symptom of many dermatological diseases (psoriasis, neurodermatitis, etc.). Itching of the skin of the legs can be caused by jaundice, which occurs for various reasons (liver and gall bladder disease, changes in hormone levels during pregnancy, etc.). Eczema and ulcers of the lower extremities are caused by vascular diseases (varicose veins) and endocrine diseases (e.g. diabetes mellitus).
Infection itching
If itching and rashes are persistent, spread throughout the body or are accompanied by general intoxication, then you should seek medical help. For example, if a red rash on the legs itches against a background of fever, intoxication and a strong general deterioration in health, then it makes sense to think about the presence of erysipelas. This skin lesion is caused by a streptococcal infection and requires treatment by a surgeon (usually the case ends with the appointment of medications and antibiotics, but it is this type of infection that is treated in the surgical departments, taking into account possible complications). The second option for this combination of symptoms is infectious diseases that may have “caught up” with you from childhood. This is chicken pox and common measles. Naturally, with erysipelas, measles and chickenpox, the itchy rash on the legs will look different. In the first case, these are reddish spots in the form of tongues of flame, in the second - merging small papules surrounded by a spot, and in the third - pink spots, turning into small and large vesicles. With such "childhood" infections, the rash spreads quite quickly throughout the body.
It should be noted that with damage to the body by fungi (mycosis) and protozoa (scabies), a itchy rash on the legs can also appear. In both cases, the itch will be "concentrated" on the fingers and in the interdigital spaces of the legs, but in the case of scabies, whitish stripes and small vesicles will appear on the skin, and the itch will intensify at night. Mycosis is manifested by peeling and papules. In addition, the scabies mite usually affects not only the feet, but the skin of the hands and abdomen.
Prevention
An itchy rash can and should be prevented. Start with a healthy lifestyle, in particular - do not eat highly allergenic foods, and in the fall and winter, support the body with vitamins. Follow personal hygiene (wash your feet daily, use moisturizer, never wear other people's clothes and shoes). When performing depilation, follow simple rules: only a sharp razor, you can not shave against hair growth, use special products, creams before and after shaving. In any case, a itchy rash on the legs is already a symptom of a disease that could have been prevented.