What causes an itchy scalp?

The most common cause of an itchy scalp is dandruff, or seborrheic dermatitis, which is believed to be caused by a combination of oily skin and overgrowth of yeast. Environmental and lifestyle factors, such as hair products, acne, stress, and obesity, appear to increase the risk of developing seborrheic dermatitis.

Many other disorders and conditions can lead to an itchy scalp, including inflammatory and autoimmune disorders, infection, allergies, and head lice. Psoriasis is a chronic inflammatory disorder caused by a problem with your immune system, but the exact cause is not known. Bacteria and yeast can infect the skin and hair follicles on your scalp, leading to an intense itch-scratch cycle.

Head lice are tiny insects that feed on blood and lay their eggs on the scalp. Head lice do not lead to serious medical problems, although they are extremely contagious and cause intense itching, which may lead to skin breakdown and possible secondary bacterial infections. An itchy scalp can also be caused by an allergy or sensitivity to hair products, including hair dye and other chemicals.

Possible causes of itchy scalp

An itchy scalp may be caused by a variety of different skin disorders and infections including:

  • Acne keloidalis nuchae (specific type of folliculitis that mainly affects males of African descent)

  • Allergic contact dermatitis or irritant contact dermatitis, such as from a hair dye

  • Dandruff or cradle cap (seborrheic dermatitis)

  • Eczema (atopic dermatitis)

  • Folliculitis (infection of a hair follicle)

  • Fungal infection (tinea capitis, ringworm) or bacterial infection of the scalp

  • Head lice

  • Hypothyroidism

  • Lupus

  • Psoriasis

  • Stress and anxiety

  • Sunburn

What are the potential complications of an itchy scalp?

In some cases, an itchy scalp can lead to complications, especially if there is severe scratching that leads to breakdown of the skin of the scalp. Scratching can introduce bacteria or fungus into the layers of skin on the scalp resulting in infections. Complications include:

  • Cellulitis (infection of the skin and surrounding tissues caused by a growing bacterial or fungal infection)

  • Hair loss, thinning hair, or bald patches

  • Open sores and lesions

Complications of underlying causes of an itchy scalp can also occur. You can best reduce the risk of complications of an itchy scalp and its underlying causes by following the treatment plan developed by you and your health care provider.


  1. Itchy Scalp or Neck. Skinsight. http://www.skinsight.com/diseaseGroups/itchyScalpNeck.htm.
  2. Seborrheic dermatitis. Medline Plus, a service of the National Library of Medicine National Institutes of Health.  http://www.nlm.nih.gov/medlineplus/ency/article/000963.htm.

What is an itchy scalp?

An itchy scalp is an inflammatory reaction of the skin underneath the hair on your head. An itchy scalp is a common problem, particularly among adults. An itchy scalp may or may not be associated with a visible rash or broken skin.

... Read more about itchy scalpintroduction


What other symptoms might occur with an itchy scalp?

An itchy scalp may occur with other symptoms, which vary depending on the underlying disease, disorder or condition. Symptoms can affect the skin and scalp and other body systems in some cases. For example, you may have joint pain if your itchy scalp is caused by psoriatic Read more about itchy scalpsymptoms

Medical Reviewer: Cynthia Haines, MD Last Annual Review Date: Aug 2, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Infections and Contagious Diseases, Eczema

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