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5 Reasons Why Your Scalp May Be Itchy

 Dr. Neera Nathan, MD, MSHS, is a board-certified dermatologist and VEGAMOUR expert. Every month, the Harvard-trained doctor shares the science behind and potential solutions to topics such as hair loss, hair growth, scalp care and graying. Read all of Dr. Nathan's articles here

An itchy scalp doesn’t always have a straightforward cause — there can be multiple reasons. But a healthy scalp is key for overall hair wellness, so figuring out the cause and finding a solution is essential. If you find yourself scratching your head, it might be one of these five possibilities. 

1. Too Many Products

While it can be tempting to use multiple styling products daily to achieve a desired look, these can contribute to scalp itch. That’s because these products inadvertently get on the scalp and can create a film on the scalp’s surface. Additionally, each day the products are applied and aren’t washed off in the shower can result in further scalp buildup. 

For example, while dry shampoo may temporarily reduce oils on the hair roots, it can also add to further buildup, in addition to sweat, excess oils and dead skin cells that accumulate on the scalp. After multiple days of not washing your hair and scalp, this film can plug scalp pores, leading to itching and inflammation. It might also cause a rash and, in some cases, hair loss.

2. Not Washing Your Hair Enough

Hair washing is really important for the scalp. Shampoo removes buildup, and conditioner may help to add moisture back to the scalp to help restore natural oils lost during the washing process. Some shampoo also has soothing ingredients which can help keep scalp itch at bay. 

That’s why it’s important to wash hair in the shower with shampoo and conditioner no less than one to two times per week — or more often if you suffer from an itchy scalp or buildup. I recommend avoiding shampoos or conditioners that contain sulfates or silicones, which have the potential to irritate and dry out the scalp.

3. Dandruff 

Dandruff is really common. It can range from white flakes on the hair strands to inflammation and scaling on the scalp with greasy buildup. All types of dandruff may cause scalp itch. We aren’t sure exactly why dandruff happens, but it seems to be linked to oil glands on the scalp and/or overgrowth of natural fungi on the scalp. Sometimes, more severe dandruff can cause a red rash that involves the scalp, face and ears, too. This is called seborrheic dermatitis. 

4. Allergies

Allergies, or allergic contact dermatitis, can cause itching and inflammation on the scalp. This can present as both itching and a red, scaly rash on the scalp. This condition generally develops upon exposure to allergens but is usually delayed and happens on repeat exposure to the triggering allergen or product. 

One common trigger of allergic contact dermatitis on the scalp is p-phenylenediamine, or PPD, which can be found in hair dyes. Other triggers include preservatives, including methylisothiazolinone (MI) /methylchloroisothiazolinone (MCI), which can be found in some shampoos and conditioners.

5. Folliculitis

Red, itchy pimples can also occur on the scalp. When pimples occur around hair follicles, they are termed folliculitis. Folliculitis can be triggered by bacteria or fungi on the scalp and might be worsened by humidity, sweat and excess oils. 

Dealing With an Itchy Scalp

If you are experiencing an itchy scalp without a rash, try increasing your frequency of hair washing, especially after sweating or using multiple products. Avoid shampoos, conditioners or hair products that contain sulfates or silicones. You may also try a deep-cleansing product that contains soothing ingredients, like zinc, directly on your scalp before shampooing. This may help to combat some of the causes of itch. If you notice redness or rash along with scalp itch, however, consult with your dermatologist. 

From Dr. Nathan: What Your Hair Can Tell You About Your Overall Health

Disclaimer: Information in this article is intended for general informational and entertainment purposes only. It is not intended to constitute medical advice, diagnosis, or treatment. Always seek professional medical advice from your physician.