While most women are aware of what can cause hair to become dry, limp, oily or brittle, few know what can cause your scalp -- an important factor in the overall health of your hair -- to become itchy. An itchy scalp can be the result of something as simple as your hair-washing habits or indicative of an underlying skin problem that requires medical attention to treat. Whatever your problems with scalp itchiness, be sure to talk to your doctor if you try and fail to control the problem at home.
Dry Scalp Skin
One of the most common causes of an itchy scalp in women is simply dried out scalp skin. Your scalp can become dry because of regular exposure to very cold or very hot weather, using hair driers too frequently and even showering or bathing in extremely hot water or spending a lot of time in the sauna. Dry scalp skin can particularly be a problem in the winter when your skin is subjected to cold, windy weather outside and dry indoor heating in buildings for days and weeks on end.
Both washing your hair too seldom and too often can cause your scalp to become itchy. If you don't wash your hair often enough, dead skin cells, oils and potentially skin-irritating substances can accumulate on the scalp. On the other hand, washing your hair too frequently -- particularly with harsh shampoos or soaps -- can cause the skin on your head to dry out and also become itchy. In addition, if you use too much shampoo while washing your hair, a residue can be left behind that may also act as a skin irritant.
Dandruff, also known as Pityriasis simplex capillitii, is a skin condition in which the scalp produces and sheds off excessive amounts of dead skin cells, making the scalp itchy. Dandruff can be caused by a wide variety of factors -- exposure to temperature extremes, mild skin infections and overactive sebaceous cells in the scalp producing too much sebum, the oily substance that prevents the hair and scalp from drying out.
Dermatitis refers to a condition that makes your skin red, inflamed and itchy. There are two types of dermatitis that can affect your scalp, making it itchy: contact dermatitis and seborrheic dermatitis. Contact dermatitis develops when the scalp skin reacts to a substance that it has come into contact with -- for instance, a hair dye, shampoo, soap, hairspray or any other hair product. You might be allergic to a compound contained in the product, or you could be reacting to the high amount of alcohol that makes up the inactive ingredients of many haircare items. High concentrations of alcohol on the skin can cause it dry out quickly and become irritated and itchy. Seborrheic dermatitis is a skin condition characterized by the overproduction of skin cells on the scalp, face, forehead, chest, neck and often abdomen and excessive dandruff. Seborrheic dermatitis can develop due to immune disorders, fungal infections and as a reaction to environmental factors. Dr. Anupam Biswas, writing for the website Health Cave, reports that genetics may also play a role.
Psoriasis is a chronic skin disease that can cause thick, itchy patches of red or silvery scaly skin to develop on various parts of the scalp, as well as on the elbows, knees and lower back. It may be caused either by the abnormally excessive production of skin cells or, as MayoClinic.com reports, by an immune system dysfunction caused by environmental or hereditary factors.
Both fungal and bacterial infections can result in an itchy, red scalp. Tinea capitis is an infection of the fungus dermophyte which infects and inflames hair shafts and causes the production of dead, flaky skin cells resembling dandruff, while lichen planus is another scalp-affecting fungal infection. Folliculitis, commonly caused by the bacteria staphylococcus aureus, is another type of infection that can cause itching and discomfort.
A number of other, more unusual factors can also cause your scalp to become itchy such as a head louse infection, also known as pediculosis capitis, too much stress in your daily life, a sunburn that causes damage on the scalp and results in the buildup of itchy, dead cells or the development of acne on the scalp.