The diagnosis of the cause of an itch can either be simple or very complex. The presenting symptom itself is diagnostic of an itch but finding the cause in some cases can be very troublesome. In all cases of prolonged itchy skin, the physician will conduct a thorough physical exam and inquire about your past medical history.
In general, very rarely is a skin biopsy rewired to make a diagnosis of an itch.
Blood tests are only relevant if an internal cause of the itch is suspected. The most common medical conditions causing an itch that a physician will look include:
Eczema: Also known as dermatitis, this essential means dry skin which is itchy. Dermatitis has numerous causes and can present in a wide variety of ways. When the skin is examined it will appear red, dry, swollen and may have scratch marks
Psoriasis: This very common skin disorder of an unknown cause frequently causes severely itchy skin. The diagnosis is not difficult as the majority of individuals have thick patches of skin with silvery scales. The disorder is common around the joints. Pain is also a common feature of psoriasis
Fungus: Another very common cause of itchy skin is fungus infections. The skin fungus can affect the groins, scalp, feet, arms or the entire body. The diagnosis can be made by looking at skin scrapping underneath a microscope
Hives: Allergic reactions typically cause minor swelling on the skin. These hives vary in size and can be intensely itchy. Hives typically occur after a drug reaction, bee sting or allergy to food products
Lice: When children present with itching, lice or scabies should always be suspected. There are no blood tests to make a diagnosis but a proper physical examination will reveal the presence of lice or their eggs. Lice can occur on the scalp, groin or anywhere else on the body.
Even though itching is not life threatening, it can be very irritating. If the itch is continuous, one may not be able to sleep or even work.
Constant itching may cause:
- thickening of the skin
- red patches on the skin
- skin breakdown
- blisters on the skin
- infection of the skin
- persistent itching can also drive someone neurotic