What is pruritus?

Pruritus is itching, an irritating skin sensation that creates the urge to scratch. It may affect one small area or become generalized across much of the body.

Itching is a symptom rather than a single disease. Common triggers include dry skin, eczema, hives, insect bites, allergic reactions, infections, and contact with irritating substances. Some internal illnesses, including liver, kidney, thyroid, or blood disorders, can also produce persistent itching without an obvious rash.

Histamine is involved in many itchy reactions, particularly allergies and hives, which is why antihistamines may help in some cases. However, not every form of pruritus is driven mainly by histamine; nerve-related or systemic itching may require different treatment.

Pruritus is often confused with a rash, but the two are not identical. A rash is a visible change in the skin, while pruritus is the sensation. Scratching may briefly relieve the urge, yet repeated scratching can damage the skin and increase inflammation. The word comes from Latin prurire, meaning “to itch.”