Itchy Scalp: Possible Causes — Answers From a Dermatologist
An itchy scalp is common and can happen for many reasons, from simple dryness to skin conditions that need treatment. The cause is often identified by looking at other symptoms, such as flakes, redness, sores, or hair changes.
1. Dandruff (seborrheic dermatitis)
One of the most common causes of an itchy scalp.
Possible signs:
- White or yellowish flakes
- Oily or irritated scalp
- Redness
- Itching that comes and goes
It is often linked to an overgrowth of a normal skin yeast called Malassezia, combined with oil production and skin sensitivity.
2. Dry scalp
A dry scalp may occur because of:
- Cold weather
- Frequent washing
- Hot water showers
- Harsh shampoos
- Low humidity
Signs:
- Small dry flakes
- Tight feeling skin
- Mild itching
3. Allergic reaction or contact dermatitis
Some people react to ingredients in:
- Hair dyes
- Shampoos
- Conditioners
- Styling products
- Fragrances
Signs:
- Sudden itching after using a new product
- Burning or redness
- Rash or swelling
4. Scalp psoriasis
Psoriasis can affect the scalp and cause:
- Thick, silvery-white scales
- Red patches
- Itching or soreness
- Flakes that may extend beyond the hairline
