Scalp Eczema - Itchy Scalp Causes & Treatment

An itchy or scaly scalp is common among the general population.^[1] A scaly scalp can lead to flaking in the hair and onto the clothes, which can be quite embarrassing. The scalp can become irritated and scaly for a variety of reasons, often causing worry about whether a scaly scalp is an indication of a bad bout of dandruff or something more serious like scalp psoriasis.

Here are a few causes for a scaling and itchy scalp:

1) Scalp Seborrheic Dermatitis 

Seborrheic dermatitis is a chronic condition that involves scaling and inflammation of the scalp. It is the classic cause for “dandruff.” The scalp flakes easily and has a greasy nature.  

Clues to this diagnosis

Seborrheic dermatitis can cause greasy and red scaling in other areas of the skin beyond the scalp:^[1]

• Eyebrows, forehead, and cheeks
• Corners of the nose
• Smile folds from the nose to the mouth
• Both behind and within the ears
• In some cases, the armpits, chest, and groin

Western and naturopathic perspectives

Seborrheic dermatitis is believed to be caused by an imbalance and overgrowth of the yeasts that naturally occur on the skin. In particular, the Malassezia species of yeast (such as Malassezia furfur, Malassezia ovalis, Malassezia globosa, and Malassezia restricta) when overgrown^[2,3] can transform the normally occurring skin oils into byproducts that cause inflammation and irritation.^[4]

Ayurvedic perspective

Seborrheic dermatitis is an imbalance in the pitta and kapha doshas. The pitta imbalance leads to the inflammation and redness while the kapha imbalance leads to the greasiness seen in this condition. The goal of therapy is to balance pitta and kapha.

Integrative approach to treatment

• Antifungal shampoos are typically used to control the overgrowth of the yeasts. One frequently used example is ketoconazole shampoo.^[1]
• Topical steroids help reduce inflammation. In more severe cases, topical steroids may be used to temporarily reduce the inflammation.^[1]
• Unmedicated oils can worsen the condition. Directly applying an unmedicated oil, such as coconut oil, may actually worsen the condition because this leads to more greasiness. From the Ayurvedic perspective, unmedicated oils and can further push kapha out of balance leading to more greasiness and scaling.
• Infused or medicated oils, on the other hand, can be beneficial for the scalp. This includes both steroids in an oil base (Western perspective) and herbally infused oils (Ayurvedic and naturopathic perspectives). One example of an herbally infused oil is neem infused coconut oil. Unlike regular coconut oil, neem infused coconut oil contains neem, which has antifungal activity against the Malassezia species of yeast.^[5]

2) Scalp Psoriasis

Psoriasis is a chronic skin condition that does not have a present cure in either the Western or Ayurvedic perspective. However, it can be well controlled with the use of lifestyle modifications and medications.

Clues to this diagnosis

Psoriasis leads to plaque-like lesions in the hair that are much thicker than seborrheic dermatitis. Although the lesions may noticeably feel thicker to the touch, it is important to seek a dermatologist to help with a proper diagnosis. Several other clues can help differentiate psoriasis from other conditions, including:

• Skin involvement in other areas like the elbows, knees, back, abdomen, hands, and legs
• Nail changes including pitting, nail separation from the finger, and lesions known as “oil-spots” on the nails
• Joint pain that may also be a sign of inflammatory arthritis
• A family history of psoriasis

Western and naturopathic perspectives

Psoriasis develops as a result of an overactive immune system. For the biology geeks, the Th17 subset of the T-cells in the immune system is overly active,^[6] leading to the inflammation and scaling skin plaques seen in psoriasis. The cause for this overly active immune system is still not fully known and under intense research.

Ayurvedic perspective

Psoriasis is known as Ekakustha in Ayurvedic medicine, and it is caused by an imbalance of all three of the doshas including vata, pitta, and kapha. There is more of an imbalance in the pitta dosha than the others, represented by the significant inflammation in psoriasis.

Integrative approach to treatment

• Topical steroids are important in reducing the inflammation of scalp psoriasis. Because the lesions can be very thick, it is important to use strong steroids initially to gain control of the psoriasis lesions^[7] and then transition to a weaker steroid. With good levels of control, steroid use can be reduced or tapered off.
• Steroids may be directly injected into the scalp psoriasis. In many cases, topical steroids are not enough to jumpstart the healing process, and an injection with steroids is required to get the psoriasis lesions under control.^[8] A dermatologist or a qualified health provider is necessary to make these assessments.
• Herbal oils can be helpful, especially when used in conjunction with steroids. Topical turmeric can improve psoriasis,^[9,10] and turmeric infused oils (such as coconut oil) may be helpful. While there are studies of topical turmeric,^[9,10] there are no studies of herbal oils for psoriasis.
• Systemic therapies may be needed if the psoriasis is severe. There are many different medications that are currently used for psoriasis (Western). Several herbs have been studied for their use in psoriasis.^[11,12]
• Phototherapy (light-based treatments) are effective in treating body psoriasis, but the scalp can be a difficult area to treat because of the hair on the scalp. An exception is the use of the excimer laser, which delivers ultraviolet therapy to focal areas on the scalp.^[8] For those who are balding or bald, generalized phototherapy may be an option.

3) Sebo-psoriasis

There is no agreed-upon definition for sebo-psoriasis. It is frequently thought to be a diagnosis for symptoms that do not fit into psoriasis or seborrheic dermatitis completely. Instead, sebo-psoriasis is an overlap between the two. Scalp plaques that are thicker than typical seborrheic dermatitis typically mark this condition. On the other hand, there are often few other findings that are consistent with psoriasis anywhere else on the body. Some clinicians feel that sebo-psoriasis is just a form of localized psoriasis.^[13]

Clues to this diagnosis

Scalp lesions can be thick. However, the nails, other parts of the skin, and the joints will appear normal. Sebo-psoriasis can affect the following areas of the skin:

• Scalp
• Behind the ears
• Along the hairline

Some people with sebo-psoriasis may have a family history of psoriasis.

Western and naturopathic perspectives

The cause for sebo-psoriasis is unknown, but it is believed to be similar to psoriasis in which an overly active immune system is involved.

Ayurvedic perspective

Sebo-psoriasis is an imbalance in the pitta and vata doshas.

Integrative approach to treatment

The treatment approach is similar to psoriasis without the use of systemic therapies:

• Topical steroids are important to reduce the scalp inflammation. Because the lesions can be very thick, it is important to use strong steroids to get it under control.^[7]
• Steroids may be directly injected into the scalp. Similar to scalp psoriasis, steroid skin injections may help to improve control of this condition.^[8] A dermatologist or a qualified health provider is necessary to make these assessments and determine if steroid scalp injections are appropriate.
• Laser treatments with ultraviolet based lasers, known as the excimer laser, can be helpful.^[8]
• Herbal oils can be helpful, especially when used in conjunction with steroids.

4) Scalp Contact Based Skin Allergy (Contact Dermatitis) 

Although it is uncommon to develop a contact allergy on the scalp, contact dermatitis is caused when the skin becomes inflamed and scaly as a result of an allergy.^[14] Some of the causes may include a shampoo, conditioner, or hair dye.

Clues to this diagnosis

Contact allergies typically develop after the skin is exposed to the chemicals that caused the allergy. Timing is everything in this case. If the flares of scalp scaling and irritation started after hair dyeing, or if the flares started after using a new hair shampoo/conditioner, hair product, or hair oil, this is a clue that an allergy may be the culprit of the rash. Even an allergy to shampoos and conditioners that have been used for years can develop over time. 

Ingredients in shampoos or conditioners that could cause an allergy include:

• Kathon CG,^[15] a mix of the preservatives methylchloroisothiazolinone and methyl isothiazolinone
• Formaldehyde releasing ingredients like quaternium-15, DMDM hydantoin, and imidazolidinyl urea^[16]
• Fragrances
• Botanicals, especially when essential oils are used to scent the shampoo

Western and naturopathic perspectives

Contact allergies develop when the skin’s immune system reacts to a chemical by responding with inflammation. This leads to itching, scaling, and redness that can be severe at times. If it is not treated appropriately, breaks can form in the skin and increase the risk for infections. 

Ayurvedic perspective

Contact allergies are considered an imbalance in pitta and vata. Pitta is responsible for the inflammation, while vata imbalance leads to the scaling and cracking nature of the skin. Ayurvedic medicine also sees this as a contact created imbalance similar to Western medicine where the skin can become overly reactive to a chemical on the skin. 

Integrative approach to treatment

• Stop exposure to the offending chemical. The cure to contact dermatitis is to find which chemical or group of chemicals is causing the allergic response. One approach is to stop all of the hair products that are being used and see if the rash improves. If hair dyes appear to bring on the rash, hair dye use can be stopped to see if that improves the rash.
• Test for skin allergies with patch testing.  Patch testing may help to check for allergies. Patch testing does not always find the allergy but it can help with figuring out what are and are not allergic chemicals. Skin patch testing is not the same thing as skin prick testing that an allergy specialist would do.
• Topical steroids can reduce inflammation and may be important to quickly improve the skin and prevent an infection.
• Oils can help to soothe the skin. Several examples include steroid based oils (Western perspective), natural oils like jojoba oil (Western and Naturopathic perspectives), or herbal oils such as turmeric infused oils (Ayurvedic and naturopathic perspectives).