What Causes Itchy Scalp?
Learn how to relieve itchy scalp, when to see dermatologist
Learn how to relieve itchy scalp, when to see dermatologist
An itchy scalp can be a real head-scratcher — both literally and figuratively. Many things can make your scalp itch, and pinpointing the exact cause isn’t always easy.
Some conditions cause a mild tingling sensation, while others may feel like your scalp is on fire.
“Managing an itchy scalp begins with knowing what is causing it,” says Alvin Coda, MD, a dermatologist at Scripps Clinic Rancho Bernardo. “Simple adjustments or at-home treatments can help. But always seek medical advice when necessary, especially if symptoms interfere with your daily life.”
Here’s an overview of the most common causes of an itchy scalp — and how to find relief.
Contact dermatitis
Contact dermatitis happens when irritants or allergens come into contact with the skin — including the scalp — and trigger an allergic reaction. This leads to itching, inflammation and sometimes a rash. Common culprits include hair dyes, shampoos and styling products.
Even “natural” or organic ingredients aren’t always safe. Plant-based oils, citrus extracts and fragrances can also cause irritation, burning or tender spots on the scalp and forehead.
To manage contact dermatitis:
- Identify and stop using the suspected product for at least a week.
- Use gentle, hypoallergenic hair care products.
“Sometimes it can be tricky to determine exactly what is causing the contact dermatitis,” says Dr. Coda. “A board-certified dermatologist can perform a patch test to help identify potential allergens, so you know which ingredients to avoid.”
Dandruff
Dandruff is a very common scalp issue that causes itching and visible flakes. It’s not harmful or contagious, but it can be frustrating.
The main cause is a yeast-like fungus called malassezia, which lives on the scalp and feeds on oils from hair follicles. Contributing factors include:
- Oily skin and hair
- Hormonal changes
- Stress and fatigue
- Nutritional deficiencies
- Infrequent hair washing
Dandruff tends to worsen in winter due to cold air and indoor heating that dry out the scalp.
Mild dandruff often improves with over-the-counter (OTC) dandruff shampoos. A more severe form, called seborrheic dermatitis, can cause intense symptoms and may need prescription treatment. If symptoms don’t improve, see a dermatologist.
Folliculitis
Hair follicles can become inflamed due to bacterial or fungal infections, a condition called folliculitis. It often results in small, itchy, painful bumps on the scalp.
- Mild cases may clear on their own.
- More persistent cases may require antibiotics or antifungal medication.
Head lice
Head lice are small, wingless insects that live on the scalp and feed on blood. They’re highly contagious and can spread quickly, especially among children.
Itching is caused by an allergic reaction to their bites. Lice spread through close contact and by sharing personal items like towels, combs and pillows — not through pets or poor hygiene.
Lice and their eggs (nits) are visible with a fine-toothed comb.
Treatment involves:
- Using an OTC or prescription lice shampoo
- Following directions carefully and repeating treatment if necessary
- Washing all clothing, bedding, and towels in hot water and drying on high heat
- Soaking combs and brushes in hot water for at least 10 minutes
“You’ll have to keep checking the scalp every day for a week or so to make sure the lice are gone,” says Dr. Coda. “Getting rid of lice can be a challenge, so don’t hesitate to call your doctor if the treatment doesn’t seem to be working.”
Scalp psoriasis
Psoriasis is a chronic autoimmune disorder that causes red, scaly patches on the skin. Around 50% of people with psoriasis will experience symptoms on their scalp.
OTC shampoos and topical treatments can help, but more severe cases may require prescription medications.
Scalp dysesthesia
Scalp dysesthesia causes uncomfortable sensations — such as itching, tingling or burning — without visible skin changes.
Potential triggers include:
- Scalp trauma or injuries
- Neurological conditions like multiple sclerosis or diabetes
- Neck conditions such as arthritis or degenerative disc disease
- Psychological stress or anxiety
X-rays or MRIs may be needed to identify structural causes. Treatments may involve physical therapy, medications for nerve pain, or stress reduction techniques.
Actinic keratosis (sun damage)
Chronic sun exposure can lead to actinic keratosis — rough, scaly patches on sun-exposed areas, including the scalp. These spots are often precancerous and may or may not itch.
Because they carry a risk of turning into squamous cell carcinoma, they should be evaluated and treated by a doctor.
Treatment options include:
- Cryotherapy (freezing)
- Topical chemotherapy creams
- Immune-modulating creams
Prevention is key: wear hats and use sunscreen on exposed scalp areas.