Pruritus
Pruritus is the clinical term for itch: the sensation that provokes scratching. It is carried by its own nerve pathways rather than being a mild form of pain, and it can occur with visible skin changes or without any at all.
Itch has a clinical name because it is a distinct sensation rather than a weak version of something else. Pruritus is carried by its own nerve fibres and processed along its own pathways, which is why it produces an urge to scratch rather than an urge to withdraw, as pain does.
Character varies and clinicians ask about it. Itch that burns or stings, as in urticaria, differs from the itch of eczema that provokes sustained scratching, and the difference is informative rather than merely descriptive.
Scratching relieves it briefly and worsens it over time, which is the central difficulty. Damage to the surface admits more of whatever provoked the reaction, producing more inflammation and more itch, and the loop closes. Anyone who has watched a patch spread over an evening has watched it run.
Pruritus can occur without any visible change to the skin at all, and that situation is approached quite differently, since the explanation may lie outside the skin entirely.
Clinicians ask whether it disturbs sleep, and the question is not conversational. Sleep disruption is one of the more reliable measures of what an itchy condition is actually costing somebody, and it correlates poorly with how dramatic the skin looks. A modest-looking rash that wakes you nightly may be the more serious problem in the room.
Last updated .