Itchy skin, also known as pruritus, develops for a number of reasons, ranging from eczema and dry skin to allergic reactions and bug bites. It also can be a sign of a serious illness. Itchy skin that lasts for an instant is annoying and uncomfortable, but unrelenting pruritus can be unbearable. The first step in finding relief is finding out why your skin is itchy.
Internal and environmental triggers cause skin cells to release several chemicals, including histamines. Histamines dilate your blood vessels and stimulate nerve fibers that produce an itchy sensation. Antihistamines block the release of histamines and thus help relieve the itch. Itching is useful because it leads you to scratch and thus remove anything that may be irritating the skin, such as an insect. Oftentimes, scratching relieves the itch only temporarily and may intensify the itching sensation.
The scope of the affected area that's itchy can be a good indicator of the cause; for example, a localized itch on your arm may simply be the result of a bug bite. On the other hand, a mole that becomes dark and itchy may indicate a malignancy. Widespread itching often is the result of an internal cause, such as an allergic reaction. Kidney failure is a common cause of overall itchiness. Severe itchiness is a symptom of other serious illnesses: hepatitis, thyroid diseases, blood disorders, jaundice and HIV. Other causes of unbearably itchy skin include reactions to medication and hormonal changes during pregnancy.
Itchiness can result from external factors that irritate the skin. Dry skin itches when the body's natural moisture dissipates, either from environmental factors such as cold weather or dry heat, or personal hygiene such as bathing too little or not enough. There are a plethora of external causes that can cause severe itchiness; irritating chemicals, insect bites, poison ivy and parasites are just a few.
It is important to treat persistent itchiness because scratching can intensify the itchy sensation, causing you to scratch harder and longer, often to the point of injuring the skin. This can lead to serious bacterial infections and even permanent scarring. Persistent scratching also can lead to neurodermititis, a condition where the skin becomes thick and leathery.
A doctor can perform several diagnostic tests to determine the cause of unbearably itchy skin and then recommend treatment. Treating the underlying illness will help relieve itchiness in the case of some diseases, such as kidney failure, anemia or thyroid problems. Oral antihistamines and corticoid steroid creams can help relieve itching from skin inflammation. Several topical ointments -- menthol lotions, calamine and camphor ointments -- offer short-term relief; moisturizing lotions, a cold compress and lukewarm baths also help. If you are suffering from severe itching and your condition is not improving, consult a medical professional.