Notalgia paresthetica

Notalgia paraesthetica or notalgia paresthetica (also known as "Hereditary localized pruritus", "Posterior pigmented pruritic patch", and "Subscapular pruritus") is a chronic sensory neuropathy. Notalgia paraesthetica is a common localized itch, affecting mainly the interscapular area (especially the T2–T6 dermatomes) but occasionally with a more widespread distribution, involving the shoulders, back, and upper chest. The characteristic symptom is pruritus (itch or sensation that makes a person want to scratch) on the back, usually on the left hand side below the shoulder blade (mid to upper back). It is occasionally accompanied by pain, paresthesia (pins and needles), or hyperesthesia (unusual or pathologically increased sensitivity of the skin to sensory stimuli, such as pain, heat, cold, or touch), which results in a well circumscribed hyperpigmentation of a skin patch in the affected area.