The skin rash causes change in normal texture of the skin and may be accompanied with itching, fever, and irritation. Rashes can be localized to one part or spread all over the body. Mostly, these skin rashes are caused by an allergic reaction, but unexplained rashes, without any apparent causes, are also very common. Fungal infections, friction, systemic infections, heat, and poor hygiene are some of the other causes of skin rashes. Many people suffer from this unexplained skin rash phenomenon.
 

It is difficult to self-diagnose the causes of a skin rash. Doctors usually look at some common signs in an unexplained rash to diagnose its causes; doctors with their experience diagnose the problem of unexplained rash by looking at the size, location, and other associated symptoms. A number of investigations help find the causes and thus manage the skin rash; in most of the cases, investigations like allergy tests really help diagnose the substance that causes rash.
 

After diagnosing the causes of a skin rash, eliminating the causes of allergy requires patience. Often, these unexplained skin rashes are seen in immunocompromised patients who need proper rash management under medical supervision. At times, these rashes precede fever due to systemic infection. While ascertaining the causes of these unexplained skin rashes, the doctors ask about history of contact with any poison or allergic substances. Symptoms like fever, swelling, and nausea help doctors diagnose skin rash.
 

You should tell your doctor if you have started any new medications, or if any member of your family is suffering from the illness to help doctors diagnose the cause of the unexplained rash. In some cases, even after extensive investigations, the causes of the skin rash may remain unexplained. Hormonal changes in women during menstrual cycles can be one of the causes. Doctors rarely diagnose this cause in early stages, and zero in on it when investigations rule out other causes.
 

If suffering from an unexplained skin rash that causes itch, you can safely have any over-the-counter anti-allergy treatment before going to the doctor for proper diagnosis. You can also apply soothing calamine lotion over the rash to avoid intense itching. One of the less common causes of unexplained rash is chronic fatigue syndrome; no proper medical investigation is available to diagnose the rash caused by chronic fatigue syndrome.