What it means
Pruritus is itching — the sensation that provokes scratching. It travels along its own dedicated nerve pathways, distinct from those carrying pain.
The clinically useful division is between itching with a rash and itching without one.
Itching with a visible rash usually reflects a skin condition: eczema, urticaria, scabies, psoriasis.
Generalised itching with normal-looking skin is the one that matters, because it can be the first sign of disease elsewhere — liver or kidney disease, thyroid disorder, iron deficiency, or a blood disorder.
In practice
Scratch marks are termed excoriations. Prolonged scratching thickens skin into leathery plaques, called lichenification.
Itching is characteristically worse at night, when there is less to distract from it.
Why it matters
Persistent generalised itching with no rash warrants blood tests — liver and kidney function, thyroid, full blood count and ferritin — rather than antihistamines alone.
Itching in pregnancy affecting the palms and soles, particularly at night, requires same-day assessment for obstetric cholestasis.
Clinically reviewed by Dr Mohammad Zubair Khan, GMC 7563469
Last reviewed
August 30, 2026