There are various factors that cause itch in the body without causing any rash. So the causes itch can be classified into two, external factors that cause itch and the internal factors that cause itch. the external factors could be simple dust allergy or cement allergy or pollen, or even dry skin in winter, those causes generalised itch, the other one is another entity called as scabies that is caused by parasitic infection transmitted from one to another. To start with there may not be any rash or anything. Coming to the internal factors that cause generalised itch without rash, it could be a marker of anaemia or people having less haemoglobin or thyroid hormone fluctuations or any alteration in liver function or renal function or any internal malignancy can mimic as generalised rash. So we need to evaluate why this generalised itch is there depending on the age of the patient.
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