Learn About Hypersensitivity Vasculitis
Hypersensitivity vasculitis is an extreme reaction to a medicine, infection, or foreign substance. It leads to inflammation and damage to blood vessels, mainly in the skin. The term is not used much currently because more specific names are considered more precise.
Cutaneous small vessel vasculitis; Allergic vasculitis; Leukocytoclastic vasculitis
Hypersensitivity vasculitis, or cutaneous small vessel vasculitis, is caused by:
- An allergic reaction to a medicine or other foreign substance
- A reaction to an infection
It usually affects people older than age 16.
Often, the cause of the problem cannot be found even with a careful study of the person's medical history.
Hypersensitivity vasculitis may look like systemic, necrotizing vasculitis, which can affect blood vessels throughout the body and not just in the skin. In children, it can look like Henoch-Schonlein purpura.
Symptoms may include:
- New rash with tender, purple or brownish-red spots over large areas
- Skin sores mostly located on the legs, buttocks, or trunk
- Blisters on the skin
- Hives (urticaria), may last longer than 24 hours
- Open sores with dead tissue (necrotic ulcers)
The goal of treatment is to reduce inflammation.
Your provider may prescribe aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), or corticosteroids to reduce inflammation of the blood vessels. (Do not give aspirin to children except as advised by your provider).
Your provider will tell you to stop taking medicines that could be causing this condition.
Miguel Gay-Gonzalez practices in Santander And Univ. Of The Witwatersrand, South Africa. Mr. Gay-Gonzalez is rated as an Elite expert by MediFind in the treatment of Hypersensitivity Vasculitis. His top areas of expertise are Vasculitis, Giant Cell Arteritis (GCA), Temporal Arteritis, Lung Transplant, and Kidney Transplant.
Thilo Gambichler practices in Bochum, Germany. Mr. Gambichler is rated as an Elite expert by MediFind in the treatment of Hypersensitivity Vasculitis. His top areas of expertise are Hypersensitivity Vasculitis, Merkel Cell Carcinoma, Melanoma, and Neuroendocrine Tumor.
Javier Loricera practices in Santander, Spain. Mr. Loricera is rated as an Elite expert by MediFind in the treatment of Hypersensitivity Vasculitis. His top areas of expertise are Vasculitis, Giant Cell Arteritis (GCA), Temporal Arteritis, and Hypersensitivity Vasculitis.
Hypersensitivity vasculitis most often goes away over time. The condition may come back in some people.
People with ongoing vasculitis should be checked for systemic vasculitis.
Complications may include:
- Lasting damage to the blood vessels or skin with scarring
- Inflamed blood vessels affecting the internal organs
Contact your provider if you have symptoms of hypersensitivity vasculitis.
Do not take medicines that have caused an allergic reaction in the past.
Published Date: April 01, 2025
Published By: Diane M. Horowitz, MD, Rheumatology and Internal Medicine, Northwell Health, Great Neck, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Dinulos JGH. Hypersensitivity syndromes and vasculitis. In: Dinulos JGH, ed. Habif's Clinical Dermatology. 7th ed. Philadelphia, PA: Elsevier; 2021:chap 18.
Stone JH. The systemic vasculitides. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 249.
Stone JH. Immune complex–mediated small vessel vasculitis. In: Firestein GS, McInnes IB, Koretzky GA, Mikuls TR, Neogi T, O'Dell JR, eds. Firestein & Kelley's Textbook of Rheumatology. 12th ed. Philadelphia, PA: Elsevier; 2025:chap 92.
Sunderkötter CH, Zelger B, Chen KR, et al. Nomenclature of cutaneous vasculitis: dermatologic addendum to the 2012 revised International Chapel Hill Consensus Conference Nomenclature of vasculitides. Arthritis Rheumatol. 2018;70(2):171-184. PMID: 29136340 pubmed.ncbi.nlm.nih.gov/29136340/.