Skin conditions commonly affect the scalp, often causing itching. The age of onset, involvement of other areas of the skin, the appearance of the scalp and exposures to new products help determine the cause of scalp itch. Topical treatments prove effective for many causes of scalp itch; oral medications may be needed for chronic conditions with scalp involvement.
Dandruff
Dandruff, with itching and dry flaking of the scalp, is a common condition. Often the scalp skin may be dry because of lack of humidity in the air or overuse of hair products, especially those containing alcohol or other drying agents. Not washing the hair regularly can also cause dandruff, as dead scalp cells and hair oils accumulate, causing itching. MayoClinic.com advises that daily shampooing with a gentle product often suffices to clear mild dandruff.
Seborrheic Dermatitis
Seborrheic dermatitis is characterized by oily skin flaking and crusting, which frequently causes persistent, intense itching. The condition commonly affects the scalp, notes the American Academy of Dermatology on the patient information website EczemaNet. Seborrheic dermatitis most commonly presents in infancy, at puberty or in later adulthood. People with HIV/AIDS or Parkinson’s disease bear an increased risk for the development of seborrheic dermatitis. Frequent shampooing with dandruff shampoos and treatment with topical corticosteroids and antifungal medications are the mainstays of treatment for seborrheic dermatitis.
Contact Dermatitis
Irritation of the scalp skin by shampoos, conditioners, hairsprays, hair dyes, permanent wave or straightening solutions and other hair products may cause contact dermatitis and itching, notes MayoClinic.com. The onset of scalp itching and flaking in relationship to use of a new hair product suggests contact dermatitis as a probable cause. Discontinuing use of the product typically leads to resolution of the condition.
Scalp Psoriasis
Psoriasis is a chronic autoimmune disorder of the skin. A mistaken attack on the skin causes an exceedingly rapid rate of new skin cell production. Patches of red irritated skin develop that are covered by characteristic silvery scales. The scalp is a common site for psoriasis involvement during periods of active disease, notes the American Academy of Dermatology on the patient information website PsoriasisNet. Itching associated with scalp psoriasis ranges from mild to intense. Treatment for scalp psoriasis depends on the severity of the condition and response. Options include topical scalp medications, psoriasis shampoos, laser therapy and oral steroids and immune system suppressants.
Head Lice
The parasitic insects Pediculus humanus capitis--head lice--live in the scalp hair and bite the scalp skin to feed. Lice bites cause an allergic reaction in the scalp, leading to intense itching, explains the Centers for Disease Control and Prevention. Small white specs tightly adhered to the hair near the scalp represent lice eggs, or nits. Treatment with medicated shampoo usually clears the infestation, resolving the associated scalp itch.
