An itchy scalp is one of the more common complaints that we all experience in life. Sometimes it is associated with irritation of the skin on the head (the scalp) while other times it is more of a nervous habit. It is human nature and a cultural norm to scratch the head when thinking, uncertain and sometimes when nervous. However, there are also various diseases and medical conditions that can contribute to an itchy scalp.
Itchy Scalp or Itchy Head
There is at times confusion whether to describe the symptom as an itchy scalp or an itchy head. While it is commonplace to refer to the scalp as the head, the term is anatomically incorrect. The head encompasses the scalp, face, under the chin and even the ears. The scalp is specifically the area at the top of the head, and more correctly the skin on this area. The scalp has a fairly unusual structure than the rest of the body. It contains hundreds of thousands of follicles from which long strands of hair grow. It is important to note that the hair strands are devoid of sensation and therefore cannot itch.
What is an itchy scalp?
An itchy scalp is any itching sensation on the scalp of the head. It does not involve the strands of hair and does not extend beyond the scalp. The condition may be associated with other symptoms like rashes on the scalp, white flaking skin, dry skin and even loss of hair. The itch typically prompts a person to scratch the head which when excessive is often considered not to be a socially acceptable habit.
Most people quite unconsciously scratch the scalp as it is within reach and not covered. In severe cases, the itching can be so excessive that the sufferer scratches all day and night and the intensity of the itch affects the quality of sleep. Some patients even resort to brushing their scalp forcefully with hard bristled hair brushes and combs in an attempt to relieve the itching sensation.
Itchy Scalp Symptoms
An itchy scalp is a symptom of some underlying condition and is not a disease on its own. The itch most often prompts a person to scratch the scalp. The itching can vary in intensity with some patients only experiencing a mild itch and others reporting unbearable itchiness of the scalp. Similarly the duration and frequency of the itch can vary. Some people may experience itchiness that persists for long periods of time. Typically though, the itch is short lived and quickly relieved with scratching.
Similarly the frequency of the episodes of itching can vary. Some people may report continuous and persistent itching that may ease slightly with scratching but is not relieved altogether even for a few minutes. Other people report intermittent itching that comes on is short episodes and may be triggered by certain factors.
Triggers of itching on the scalp
Some of these triggers that worsens or brings on itching may include :
- Wearing a hat or cap
- Hot weather
- Direct sunlight exposure
- After washing the scalp of the head
- Using certain hair care and styling products
- During the application of hair dyes
- Eating certain foods (sometimes)
- Nervousness or anxiety
Other Symptoms with an Itchy Scalp
There are various other symptoms that may accompany itching of the scalp. This includes :
- Dryness of the scalp
- Flaking of the skin
- Skin rash and raised lesions like pimples, plaques, nodules, boils
- Burning sensation
- Pain on the head
- Thinning of the hair
- Hair loss (baldness)
- Changes in hair color (rare)
Itchy Scalp Causes
The most common cause of an itchy scalp that is usually intermittent, easily relieved with scratching and does not present with other symptoms is largely unknown. It is a common occurrence in life and there is often no explanation for the itchiness. In most of these instances it is not a cause for concern unless the condition recurs very often and presents with other symptoms.
One of the leading causes of an itchy scalp, poor hygiene of the hair on the head allows accumulated dirt to remain on the scalp and irritate the skin. This is further aggravated by hair care products such as hair oils and styling gel. The hair traps thousands of bacteria in the environment on a daily basis and should these bacteria be given the right conditions to thrive, it can also infect the scalp.
Braids, Extensions and Dyes
Hair styling that tends to discourage a person from washing their hair is another leading problem in patients with an itchy scalp. In the attempt to prevent undoing the style or weakening it, a person may avoid washing. Furthermore these styling products may act as irritants to the skin on the scalp further exacerbating the build up of dust and microbes from the environment.
Dry Skin on the Scalp
Dryness of the skin anywhere on the body is the most common identifiable cause of itchiness. The scalp is no different. Although natural oil (sebum) is secreted from the sebaceous gland that is connected to the hair follicle, it may sometimes be insufficient to moisturize the skin on the head. Dry skin is prone to dandruff and infections.
Dandruff is flaking off skin from the scalp. It typically appears as small white dots but can flake off in larger pieces similar to scales. Dandruff is not just a matter of dry skin as is often thought. It is a result of an abnormal immune response to a naturally occurring fungus on the head known as Malassezia furfur (Pitysporum ovale) result in a condition of excessive sebum production and the development of a condition known as seborrheic dermatitis. In infants, seborrheic dermatitis is known as cradle cap.
Scalp Fungal Infection
Tinea capitis, commonly known as scalp ringworm, is a condition where a fungus infects the skin on the scalp. It is a superficial infection most commonly caused by a type of skin fungi known as dermatophytes. Yeasts can also infect the scalp although this is less common. Tinea capitis tends to occur on the scalp when the skin is injured or damaged often due to some other underlying skin condition.
Psoriasis on the Scalp
Psoriasis is a severe chronic skin condition where the skin thickens as a result of the cells not sloughing off normally. It is also exacerbated by inflammation and infections. Psoriasis can occur anywhere on the body and the scalp is one of the commonly affected sites. It may lead to hair loss in severe cases. The condition is usually intensely itchy.
Eczema is a very broad term but usually refers to atopic dermatitis. This is an immune hypersensitivity reaction on the skin. Here the immune system abnormally reacts to certain harmless substances (allergens) thereby eliciting inflammation of the skin. It is more commonly seen in infants and young children as it starts in the early years of life. It can however, persist throughout life. Ingested allergens (foods and drinks) and inhaled allergens (in the air) are trigger but not causes.
Folliculitis is a bacterial infection of the hair follicles. It can occur anywhere in the body. With the scalp having abundant hair follicles, it is more likely to be affected with bacterial infections. Normally such infections do not arise but skin diseases affecting the scalp, poor scalp hygiene and a weak immune system can increase the risk of folliculitis. Certain hair care products that act as irritants and lifestyle measures can also increase the risk of folliculitis.
Allergies to Hair Dyes
Hair dye allergies are a problem for people the world over. It affects only a small proportion of people using hair dyes and is largely attributed to the presence of PPD (paraphenylenediamine) that is commonly used in these hair dye products. Although these chemical can irritate any person’s skin, it is more likely to be a problem in a person with skin sensitivity. In this instance it can be the cause of irritant contact dermatitis (affect any person) or allergic contact dermatitis (affect only sensitive individuals).
Head lice also known as pediculosis capitis is infestation of the scalp with tiny wingless insects. It is more common among school going children. Head lice is not an issue with personal hygiene but often spread from person to person when there is close contact. The condition is also commonly known as nits and lice, with nits referring to the eggs and immature form of the adult louse.
Acne Necrotica Miliaris
Acne necrotica miliaris is a rare condition that causes hair loss and is marked by the presence of pustular pimples on the scalp. The condition is also known as tycoon’s cap. It is a very itchy scalp condition and often mistaken as acne vulgaris on the scalp.
An itchy scalp is a common symptom of nervousness and anxiety. It is often short lived and eases once the stressful situation allays. In fact, it is common for any person to scratch their scalp when thinking, concentrating or undergoing stress. However, when there are psychological causes then it more be common. Psychogenic itchy scalp can occur even though there is no physical cause for the itch. It may associated with certain nervous habits like compulsive hair pulling (trichotillomania).
Itchy Scalp Pictures
The following pictures have been sourced from Wikimedia Commons.
Picture of scalp ringworm
Picture of seborrheic dermatitis (adult scalp)
Picture of cradle cap (infant)
Itchy Scalp Diagnosis
The clinical presentation along with a medical history may initially provide a differential diagnosis. This means that it indicates the most likely causes of an itchy scalp. Further investigation may be necessary to confirm the diagnosis.
- Skin scrapings
- Skin biopsy
- Allergy patch testing
- Examination with a Wood’s lamp
Sometimes the best way to reach a diagnosis is to stop using all hair care products and gradually re-introducing one at a time. Frequent hair washing should also be undertaken.
Itchy Scalp Treatment
There is no specific treatment for an itchy scalp. Since itchiness of the scalp is a symptom of some underlying disease, treatment has to be directed at the root cause.
- Antifungal shampoos may be prescribed for tinea capitis.
- Antibiotics may be necessary for folliculitis.
- Anti-dandruff formulation are useful for seborrheic dermatitis.
- Antihistamines may be necessary to relieve the itching associated with allergies.
- Corticosteroids may be used for more severe chronic inflammatory skin conditions.
- Frequent brushing with fine hair combs along with antiparasitic agents containing permethrin and malathion can treat head lice.
Itchy Scalp Prevention
Prevention, like treatment, of an itchy scalp depends on the root cause. Some general preventative measures that may be useful in most cases of an itchy scalp includes :
- Washing the scalp and hair frequently with mild shampoos like baby shampoo. Wash at least 2 to 3 times a week. Daily washing can cause dryness of the scalp and exacerbate the itching.
- Limit the use of hair care products like hair oils and styling gels.
- Avoid hair dyes altogether especially if one has a sensitivity to these products.
- Do not brush the scalp too vigorously and use a soft bristled brush.
- Avoid the use of braids and hair extensions as these products can irritate the scalp.
- Use head wear when in intense sun as the skin on the scalp is just as prone to sun damage.