Itchy Scalp: What Causes It? Seborrheic Dermatitis • Psoriasis • Tinea Capitis • Head Lice

3 days ago

21 min read

An itchy scalp (scalp pruritus) is itching of the scalp skin that can come from many conditions, not only dandruff. The most common causes are dandruff and seborrheic dermatitis, followed by scalp psoriasis, scalp ringworm (tinea capitis), head lice, scalp folliculitis, and allergy to hair dye or shampoo (contact dermatitis). Each condition looks different on the scalp and needs a different medicine. If you have used an anti-dandruff shampoo for 4 weeks and are not better, it may not be dandruff, and you should see a dermatologist.

This article explains how to tell apart a flaky itchy scalp, an itchy scalp without dandruff, an itchy scalp with bumps, an itchy scalp after hair dyeing, a prickling feeling as if something is crawling, an itchy nape, and itching together with hair loss. It also covers which types you can manage yourself, which need a doctor, and which medicines dermatologists use, at what strength and for how long.

What can cause an itchy scalp?

Scalp itching is a symptom, not a diagnosis, much like a cough can come from a cold or from allergy. The causes fall into 10 main groups.

Dandruff and seborrheic dermatitis (dandruff / seborrheic dermatitis) are the most common. Dandruff affects about half of adults at some point in life, while seborrheic dermatitis with clearly red patches affects about 1–5%.
Scalp psoriasis About 45–80% of people with psoriasis have scalp patches, and for some the scalp is the first or only site.
Scalp ringworm (tinea capitis) is most common in children aged 3–7 years and often comes with patchy hair loss.
Head lice (pediculosis capitis) are common in school-age children and cause intense itching at the nape and behind the ears.
Scalp folliculitis causes small red bumps or pustules at the base of hairs.
Contact dermatitis from hair dye, perming or straightening solutions, shampoo, hair-growth serums, or fragrance in products.
Dry scalp from dry air, air-conditioned rooms, washing the hair too often, or very hot water.
Neuropathic itch (scalp dysesthesia / neuropathic itch) is a prickling or burning itch with no visible rash, often linked to stress or the neck spine.
Chronic itchy rash from scratching (lichen simplex chronicus) is skin thickened by scratching the same spot again and again, most often at the nape.
Scarring hair loss diseases such as lichen planopilaris, frontal fibrosing alopecia or discoid lupus, in which itching or burning comes before permanent hair loss.

In addition, itching all over the body, including the scalp, may come from internal conditions such as thyroid disease, liver disease, kidney failure, iron deficiency, or medicine side effects. Doctors think of these when the itch is in many places and no rash is found.

How to tell the cause of an itchy scalp from what you see

Part your hair in good light, or ask someone at home to look, then compare with the descriptions below.

Yellow, greasy flakes on a faintly red base with unclear edges that spread to the eyebrows, beside the nose and behind the ears → think of seborrheic dermatitis.
Thick silvery-white scales on raised red patches with clear edges, extending beyond the hairline onto the forehead or behind the ears → think of psoriasis.
Round patches of hair loss with broken hairs like stubs and grey scales, especially in children → think of fungal infection.
Tiny white or brown dots stuck to the hair no more than 6 mm from the scalp that do not flick off → think of lice eggs (nits).
Small red bumps or pustules with a hair in the centre → think of folliculitis.
Red, swollen, itchy or weeping rash appearing 1–3 days after hair dyeing or changing shampoo, spreading to the forehead, ears and neck → think of contact allergy.
Nothing visible, normal-looking skin, but prickling, burning or a crawling feeling → think of dry scalp or neuropathic itch.
Thick, rough, darker skin in a single patch at the nape → think of chronic itchy rash from scratching.
Hair thinning in an area, smooth shiny skin with no visible follicles, and redness or a collar of scale around hair bases → think of scarring hair loss, which needs a doctor soon.

Looking with the eyes helps narrow things down, but many conditions overlap in appearance, for example seborrheic dermatitis and psoriasis together, called sebopsoriasis. So do not use strong steroid medicines or lice treatments on your own before you know what you have.

Itchy scalp from dandruff and seborrheic dermatitis (Seborrheic dermatitis)

What it looks like: White to yellow, fairly greasy flakes that fall onto the shoulders. In seborrheic dermatitis the skin underneath is also red, and it is often found on the eyebrows, beside the nose, behind the ears or on the middle of the chest. It tends to come and go, and gets worse with stress, lack of sleep or weather changes.

Cause: The skin reacts to Malassezia, a yeast that normally lives on the skin, together with oil on the scalp. It is not an infection caught from other people and is not caused by unclean hair washing.

Severity/urgency: It is not dangerous and not contagious, but it is a long-term condition that can be controlled and may come back, so medicines are used in courses with a maintenance shampoo afterwards.

When to see a doctor: No improvement after 4 weeks of using a medicated shampoo correctly, the rash spreads to the face, or it is so red and thick that it cannot be told apart from psoriasis.

Itchy scalp from psoriasis (Scalp psoriasis)

What it looks like: Raised red patches with clear edges, covered with thick silvery-white scales; picking them off may cause tiny pinpoint bleeding. They often extend about 1–2 cm beyond the hairline at the forehead, temples, behind the ears and at the nape. Some people also have small pits in the nails, or patches on the elbows and knees.

Cause: An overactive immune system makes skin cells multiply several times faster than normal. Genetics play a part. Triggers include stress, scratching, throat infections, alcohol, smoking and some medicines. It is not contagious.

Severity/urgency: It is not an emergency, but if you also have joint pain, swollen finger joints or misshapen nails, psoriatic arthritis should be assessed within a few weeks because joints can be permanently damaged.

When to see a doctor: Very thick scales, anti-dandruff shampoo not working, a rash spreading beyond the hairline, or a rash elsewhere on the body.

Itchy scalp from fungus (Tinea capitis, or scalp ringworm)

What it looks like: Round or patchy hair loss, hairs broken close to the scalp leaving stubs or black dots, and grey scales. Some people develop a soft, raised, pus-filled lump (kerion) and swollen lymph nodes at the back of the neck. It is most common in children aged 3–7 years and less common in adults.

Cause: Dermatophyte fungi, passed on by sharing combs, hats or pillows, or from pets such as cats and dogs.

Severity/urgency: It needs treatment with tablets, because creams alone do not reach the hair root. If a kerion is left untreated, it may leave a scar and permanent hair loss in that spot.

When to see a doctor: A child with an itchy scalp together with patchy hair loss, broken hair stubs or a pus-filled lump on the scalp should see a doctor within 1–2 weeks and should not wait.

Itchy scalp from head lice (Head lice)

What it looks like: Intense itching at the nape and behind the ears, often worse at night. Nits are white or brown oval dots stuck firmly to the hair and do not flick off, unlike dandruff, which brushes away easily. You may see fast-moving lice 2–3 mm long. Some people have red bumps or scratch marks on the back of the neck.

Cause: Spread by head-to-head contact, sharing a pillow, or sharing combs and hats. Lice do not jump or fly and can survive only 1–2 days off the scalp. Nits hatch in 7–10 days.

Severity/urgency: Not dangerous, but spreads quickly through the household and the classroom. If scratching causes sores, a secondary bacterial infection may develop.

When to see a doctor: Live lice are still found after 2 rounds of treatment, a child under 2 years, a pregnant woman, or an infected sore on the scalp.

Read how to spot nits and clear them from the whole household at What causes head lice, how to spot nits and tell them from dandruff

Itchy scalp with bumps: scalp folliculitis (Scalp folliculitis)

What it looks like: Red bumps or pustules 1–5 mm wide with a hair in the centre, itchy or painful when combing. They are common along the front hairline and at the nape. The bumps burst and form crusts, and some people get them repeatedly for months.

Cause: There are several types: the bacterium Staphylococcus aureus, Malassezia yeast (often very itchy, with bumps of similar size), blockage from hair oil, gel or wax, and scratching or shaving the head. In dark-skinned men with very short shaved hair, a type that leaves raised scars at the nape may occur.

Severity/urgency: Mostly not dangerous, but if bumps merge into pus-filled lumps, cause severe pain or fever, or lead to permanent hair loss where they keep recurring (folliculitis decalvans), it needs serious treatment.

When to see a doctor: Bumps recurring for more than 4–6 weeks, abscesses or pus-filled lumps, fever, or hair beginning to thin where the bumps are.

Itchy scalp after hair dye, or still itchy after washing: contact dermatitis of the scalp (Contact dermatitis)

What it looks like: Itching, burning and a red scalp, possibly with clear blisters, weeping and crusts, spreading to the hairline, forehead, ears, eyelids and neck, where the product runs down. In the allergic type, symptoms usually appear 1–3 days after contact. In the irritant type, burning usually starts at once or within a few hours.

Cause: Common culprits are paraphenylenediamine (PPD) in dark hair dyes, including black henna, which is often mixed with PPD; chemicals in perming and straightening solutions; fragrance; preservatives in shampoo; and some hair-growth products containing propylene glycol. People allergic to PPD may also react to temporary tattoo dyes and some chemicals in ink or rubber. "Still itchy after washing" or "itchy after changing shampoo" may therefore be an ingredient allergy, not unclean hair.

Severity/urgency: If the face or eyelids swell a lot, breathing is difficult, or blisters spread fast, go to a hospital at once. A mild case usually improves within 1–3 weeks after stopping the allergen.

When to see a doctor: The rash spreads beyond the scalp, weeps, the face swells, or it returns every time you dye your hair. A patch test should be done to find out which substance you are allergic to and what to avoid in future.

Itchy scalp without dandruff, a prickling feeling as if something is crawling: dry scalp and neuropathic itch

This group is people who tell the doctor, "My head itches all day but there is nothing to see." There are 2 main types.

Type 1: Dry scalp (dry scalp)

What it looks like: Fine, white, dry, non-greasy flakes with no red base. The skin on the arms and legs is often dry too. It is worse in winter or in people who stay in air-conditioned rooms all day.

Cause: Washing the hair several times a day, very hot water, shampoo with strong detergents, or a hot hairdryer close to the scalp, which strip the natural oils that protect the skin.

Severity/urgency: Not dangerous. It usually improves within 1–2 weeks once the washing routine is adjusted.

When to see a doctor: Still itchy 2–3 weeks after adjusting your washing, or a red rash begins.

Type 2: Neuropathic itch (scalp dysesthesia)

What it looks like: Prickling, burning, numbness or a feeling of insects crawling on the head while the scalp looks normal. It is worse with stress, lack of sleep, or after sitting with the neck bent for a long time. It is most common in middle-aged women.

Cause: The sensory nerves of the scalp send abnormal signals. Studies have found links with neck spine degeneration and tight neck muscles. Stress, anxiety and depression make the symptoms more noticeable.

Severity/urgency: Not harmful to the body, but it disturbs sleep and quality of life. Anti-dandruff shampoo and antifungal medicines do not help because it is not caused by a germ.

When to see a doctor: Itching continuing for more than 6 weeks with no rash, no improvement after several products, or numbness or pain shooting from the neck down the arm.

If there is nothing to see on the scalp but the whole body itches too, a doctor may check blood tests for liver, kidney and thyroid function, iron level and blood sugar, because itching from internal disease often has no visible rash.

Itchy nape with thickened skin from scratching: lichen simplex chronicus (Lichen simplex chronicus)

What it looks like: A thick, rough patch at the nape or back of the neck, darker than the surrounding skin, with skin lines that look like tree bark. Hair there is thin or broken from scratching. The itch comes in bouts and is worse at night or when stressed.

Cause: It starts as a mild itch from any cause, then repeated scratching thickens the skin and makes the nerves more sensitive to itch, creating a cycle of "itch → scratch → thicker skin → more itch".

Severity/urgency: Not dangerous, but it lasts for months or years if the scratching cycle is not broken.

When to see a doctor: The skin at the nape keeps getting thicker, or the itch stops you sleeping.

Itchy scalp with hair loss: warning signs that need prompt examination

Itching with hair loss is mostly due to seborrheic dermatitis or scratching, and the hair grows back once the itch is controlled. But some diseases permanently destroy the hair root.

What it looks like: Hair thinning in an area, with smooth, shiny skin and no visible follicles, and a collar of scale or redness around the remaining hairs. The front hairline recedes along with thinning eyebrows, or recurring pustules appear on the crown. Itching, burning or pain often comes first.

Cause: The group of scarring hair loss diseases (cicatricial alopecia), such as lichen planopilaris, frontal fibrosing alopecia, discoid lupus erythematosus and folliculitis decalvans, as well as severely inflamed scalp ringworm.

Severity/urgency: Hair lost because the hair root has scarred does not come back. Treatment aims to stop further spread, and the earlier it starts, the more hair is kept.

When to see a doctor: Within 2–4 weeks of noticing a patch of thinning hair with smooth, shiny skin, or a receding hairline with itching and burning. The doctor usually needs to examine the scalp with a magnifying scope, and some people need a small 4 mm skin biopsy.

Read about the causes of each type of hair loss at What causes hair loss, which kinds recover on their own and which become permanent if left alone

Why is my scalp itchy at night?

Many skin conditions itch more at night, which does not mean a serious disease. The reasons are that skin temperature rises under the covers, levels of cortisol, a hormone that reduces inflammation, fall at night, and nothing else distracts you. Causes that stand out for night-time scalp itch are

Head lice: lice move more in the dark and cause intense itching at the nape.
Chronic itchy rash from scratching at the nape, which people often scratch in their sleep without noticing.
Allergy to pillowcases or to scented laundry detergent and fabric softener.
Dry scalp from sleeping in an air-conditioned room with low humidity.
Neuropathic itch, which becomes more noticeable with stress or poor sleep.

If you itch all over at night, not just on the head, and others in your household itch too, think of scabies. If whole-body itching comes with night sweats, fever or weight loss, see a doctor to check for internal disease.

Which scalp itch is cancer or a sign of serious disease?

Scalp itching alone is almost never the first sign of cancer, but some signs should be checked by a doctor promptly.

A sore, bump or lump on the scalp that does not heal within 4 weeks, grows, bleeds easily or keeps forming a crust in the same place, especially in people who are bald or have thin hair and a lot of sun exposure. It may be basal cell or squamous cell skin cancer.
A mole or dark spot on the scalp with uneven edges, uneven colour, a size over 6 mm, or fast change.
Itching all over the body including the scalp together with fever, heavy night sweats, weight loss of more than 10% in 6 months, or enlarged lymph nodes you can feel. The doctor will check for lymphoma and other internal disease.
Chronic red patches in many places, on the body and scalp, that have not responded to steroid creams for several months. It is very rare for this to be a type of lymphoma of the skin.

If none of these signs are present, almost all scalp itching comes from treatable skin conditions and there is no need to worry excessively, but you should know the cause so you can use the right medicine.

How does a dermatologist look for the cause of an itchy scalp?

Most of the examination can be done in a single visit and is painless.

Taking a history When the itch started, where it is, whether you recently dyed, permed or straightened your hair or changed shampoo, whether others at home itch too, whether you have rashes elsewhere, joint pain or hair loss, and which medicines you have already used.
Looking at the scalp and other skin such as the eyebrows, behind the ears, elbows, knees and nails, which often show whether it is seborrheic dermatitis or psoriasis.
Magnified scope examination (dermoscopy or trichoscopy) looks at blood vessels, scales, follicles and hair shafts. It helps separate psoriasis from seborrheic dermatitis, shows nits clearly, and shows whether the hair roots are scarred.
Skin scraping for fungus (KOH) takes only a short time, and a culture may be sent with results in about 2–4 weeks. In a child with suspected scalp ringworm it should be done before starting tablets.
Pus culture in recurrent folliculitis, to choose an antibiotic that matches the germ.
Patch test where test substances are taped to the back for 48 hours and read at 48 and 72–96 hours, for people who suspect an allergy to hair dye or products.
Skin biopsy of about 4 mm, only when scarring hair loss is suspected or a lump needs to be checked for cancer.

Medicated shampoos for an itchy scalp: which to use and how to get results

Medicated shampoo is the main treatment for itching from dandruff and seborrheic dermatitis, and helps as an add-on in scalp ringworm. The most common mistake is washing it off straight away, so the medicine has no time to work.

How to use a medicated shampoo properly: Wet the hair, apply the medicated shampoo directly to the scalp, not the ends of the hair, massage gently and leave it on for 3–5 minutes before rinsing. Use it 2–3 times a week for 2–4 weeks in a row, then reduce to once a week, or once every 1–2 weeks, to keep it from coming back. On other days, use an ordinary gentle shampoo.

Medicines dermatologists commonly use (listed by generic name)

Ketoconazole 2% reduces Malassezia yeast, is the mainstay for seborrheic dermatitis, and is used to help reduce spread in scalp ringworm.
Selenium sulfide 1–2.5% reduces yeast and skin shedding. It may slightly change the colour of dyed or light-coloured hair.
Ciclopirox 1% works against fungus and reduces inflammation. It is used as an alternative when ketoconazole does not work.
Zinc pyrithione 1–2% is milder, and suits long-term control.
Salicylic acid 2–6% helps dissolve thick scale and is often used in psoriasis. Use it before other shampoos so the medicine can soak into the skin better.
Coal tar 0.5–5% reduces skin shedding and itching in psoriasis and thick seborrheic dermatitis. It has a strong smell and may dull light-coloured hair.
Clobetasol propionate 0.05% shampoo is a high-potency steroid used for scalp psoriasis. Unlike other shampoos, you apply it to the dry scalp, leave it on for 15 minutes, then rinse off, once a day for no more than 4 weeks, then reduce how often you use it. Use only as prescribed by a doctor.

If you have used a medicated shampoo correctly for a full 4 weeks and are not at least half better, the diagnosis should be reviewed, rather than switching shampoos over and over.

Medicines to apply for an itchy scalp, chosen by cause

Scalp medicines usually come as lotions, solutions, foams or gels, because they pass through hair better than creams.

Steroids for the scalp such as betamethasone valerate 0.1% lotion or mometasone furoate 0.1% lotion, used once or twice a day while the itch and redness are marked. This is generally 1–2 weeks for seborrheic dermatitis and contact dermatitis, and 2–4 weeks for psoriasis, then reduced to every other day or only on days with symptoms. Using them continuously for months without consulting a doctor can thin the skin and cause a rash that no longer responds to treatment.
Combination calcipotriol and betamethasone dipropionate gel for scalp psoriasis, applied once a day for up to 4 weeks, then used in courses to keep it under control.
Antifungal lotion or foam such as ketoconazole 2%, used for seborrheic dermatitis when you do not want to use a steroid for long.
Clindamycin 1% lotion twice a day for 2–4 weeks for mild bacterial folliculitis.
Anti-itch preparations for nerve itch such as creams or lotions with menthol 1% or pramoxine, which give temporary relief and are used as an add-on in dry scalp and neuropathic itch.

Lice treatments:

Permethrin 1% lotion or cream rinse, applied to shampooed, towel-dried hair over the whole scalp, left for 10 minutes then rinsed off. Repeat on day 7–10 to kill lice newly hatched from eggs. Resistance to this medicine has been reported in many countries.
Dimeticone 4% lotion that suffocates lice and is not an insecticide. Leave on as the label says, usually about 8 hours or overnight, and repeat after 7 days.
Ivermectin 0.5% lotion applied to dry hair for 10 minutes then rinsed off, used only once. Oral ivermectin is used only for resistant cases as prescribed by a doctor.
Use together with combing with a fine-toothed lice comb on wet hair every 3–4 days for 2 weeks, and check everyone in the household at the same time.

Tablets a doctor may use

Tablets are not the main treatment for most scalp itching, but they are needed in some conditions.

Scalp ringworm: Griseofulvin at about 20–25 mg/kg/day, taken with a fatty meal for 6–8 weeks, or terbinafine, dosed by body weight, for 4 weeks. The doctor chooses the medicine by the type of fungus, and usually has the patient and the household also use an antifungal shampoo. Treatment is judged successful when the culture is negative, not just when the itch stops.
Recurrent folliculitis or pus-filled lumps: Oral antibiotics such as doxycycline 100 mg once or twice a day for 4–8 weeks, guided by the culture result. For the type caused by yeast, a short course of oral antifungal may be used.
Severe contact dermatitis that spreads to the face or swells the eyes: The doctor may give oral prednisolone for a short time, then taper the dose, for about 1–3 weeks.
Neuropathic itch: Medicines that modulate nerve signalling, such as low-dose amitriptyline 10–25 mg at bedtime, or gabapentin, starting low and increasing slowly. It usually takes 4–8 weeks to see an effect.
Severe scalp psoriasis with a rash covering more than half the scalp, no improvement after 8 weeks of creams, or joint inflammation as well. The doctor may consider immunosuppressive medicines or biologics, which need blood tests for monitoring.
Sedating antihistamines help you sleep without scratching in the early days, but they do not treat the cause, and should not be used in older adults without consulting a doctor.

The choice of medicine, dose and duration is for the examining doctor to decide. The information above is meant to help you understand how each condition is treated differently, and you should not buy these medicines to use on your own before the cause is known.

How do I stop my scalp itching? Self-care at home

While waiting to see a doctor, or if the itch is mild, the things that really help are

Wash your hair no more than once a day with warm, not hot, water. If you have greasy flakes from seborrheic dermatitis, do not skip washing for more than 2–3 days, because built-up oil lets yeast increase.
Use a medicated shampoo properly by leaving it on for 3–5 minutes before rinsing, 2–3 times a week.
Stop new products you started in the 1–2 weeks before the itch, such as shampoo, treatments, serums and hair oils.
Blow-dry with warm or cool air about 15 cm from the scalp, and do not go to bed with wet hair.
Keep your nails short and, if the itch is strong, press or apply a cold compress for 5–10 minutes instead of scratching.
Change your pillowcase every 2–3 days while you have symptoms, and use a fragrance-free laundry detergent.
Reduce stress and get enough sleep, because seborrheic dermatitis, psoriasis and neuropathic itch all flare easily with stress or lack of sleep.
If you think it is head lice check everyone in the household, wash pillowcases and towels in hot water, or seal items that cannot be washed in a bag for 2 days.

What not to do when your scalp itches

Do not scratch with fingernails or a sharp-toothed comb, because it causes sores, secondary infection and thickened skin.
Do not apply lime (makrut) juice, vinegar or strong essential oils to an inflamed scalp. These irritate and can add to allergy. Coconut oil or olive oil may make seborrheic dermatitis worse, because the fat feeds the yeast.
Do not use lice treatments repeatedly, more often than the label says, because they irritate the scalp and make it itch more, and can make you wrongly think it has not cleared.
Do not use a steroid cream bought on your own for several weeks, especially if you do not yet know it is not a fungus, because steroids make fungus spread and harder to diagnose.
Do not dye, perm or straighten your hair again while the scalp is still inflamed. Wait until it has fully healed, at least 2–4 weeks.

When should you see a dermatologist?

See a doctor if any one of the following applies

Still itchy after using a medicated shampoo correctly for a full 4 weeks
Itching together with patchy hair loss, thinning hair or a receding hairline
A child with round patches of hair loss, broken hair stubs or a pus-filled lump on the scalp
Thick silvery scales, a rash spreading beyond the hairline, or a rash on the elbows and knees or abnormal nails
A red, swollen, weeping rash after hair dyeing or using a new product, especially if the face or eyelids swell
Recurrent pustules, lumps, pain or fever
Itching so bad that you cannot sleep for more than 2 weeks in a row
A sore or lump on the scalp that does not heal within 4 weeks

Read other related skin condition articles at Skin condition article hub

In brief

An itchy scalp is a symptom, not a disease. The most common causes are dandruff and seborrheic dermatitis, followed by psoriasis, fungus, lice, folliculitis and allergy to hair dye.
Yellow greasy flakes suggest seborrheic dermatitis, thick silvery scales with clear edges suggest psoriasis, round patches of hair loss in a child suggest fungus, and dots stuck firmly to the hair suggest nits.
An itchy scalp without dandruff may be dry scalp, product allergy or neuropathic itch, which anti-dandruff shampoo does not help.
Medicated shampoo must be left on for 3–5 minutes, 2–3 times a week for 2–4 weeks. If there is no improvement within 4 weeks, see a doctor.
Scalp ringworm needs tablets for 4–8 weeks, and lice need a second round of treatment on day 7–10.
Itching with hair thinning where the skin looks smooth and shiny, or a sore that does not heal within 4 weeks, calls for seeing a dermatologist promptly.

Frequently asked questions about an itchy scalp

Why is my scalp itchy but I have no dandruff?

An itchy scalp with no visible flakes is usually due to 4 causes: dry scalp from frequent washing or very hot water; allergy or irritation from a recently changed shampoo, hair dye or serum; early-stage lice with few nits yet; and neuropathic itch (scalp dysesthesia), a prickling or burning itch that is stronger with stress or after long periods with the neck bent. In these cases anti-dandruff shampoo usually does not help. Try stopping new products and washing with warm water no more than once a day. If it still itches after 2–3 weeks, a dermatologist should examine the scalp with a magnifying scope to find the cause.

How do I stop my scalp itching?

You need to know the cause first, because each condition uses a different medicine. If there are greasy flakes and a red base, use a medicated shampoo with ketoconazole 2% or selenium sulfide, left on for 3–5 minutes before rinsing, 2–3 times a week for 2–4 weeks. If the itch began after hair dyeing or changing shampoo, stop that product at once. If you see nits stuck firmly to the hair, you need two rounds of lice treatment 7–10 days apart. Meanwhile keep your nails short and use a cold compress instead of scratching. If there is no improvement in 4 weeks, or you also have hair loss, see a dermatologist.

Why does it feel like something is crawling on my head?

A feeling of something crawling on the head can be of 2 kinds. The first is real lice: part the hair at the nape and behind the ears in good light, and if you see white or brown oval dots stuck firmly within 6 mm of the scalp that do not flick off, they are probably nits. The second is when nothing is really there but the scalp nerves send abnormal signals, called scalp dysesthesia, usually with prickling, burning or numbness, and worse with stress or lack of sleep. Lice treatments and anti-dandruff shampoo do not help in this case. A doctor may use a low dose of a nerve-modulating medicine along with managing stress and neck posture.

Which kind of itch is cancer?

Scalp itching alone is almost never a sign of cancer. Things to watch for are a sore, bump or lump on the scalp that does not heal within 4 weeks, grows or bleeds easily; a mole that changes shape or colour; and whole-body itching with fever, heavy night sweats, weight loss of more than 10% in 6 months, or enlarged lymph nodes, which should be checked for lymphoma and other internal disease. If none of these are present, almost all scalp itching is due to treatable skin conditions such as seborrheic dermatitis, psoriasis, fungus or product allergy.

Which shampoo is best for an itchy scalp?

Choose by cause. For dandruff or seborrheic dermatitis with greasy flakes, the main ingredients are ketoconazole 2% or selenium sulfide 1–2.5%. Ciclopirox 1% is used as an alternative when the first does not work. For thick psoriasis-type scale, a salicylic acid or coal tar shampoo may help dissolve the scale, and the doctor may prescribe clobetasol 0.05% steroid shampoo applied to dry hair for 15 minutes. If the itch is from dry scalp or allergy, use a gentle fragrance-free shampoo. The key is to leave a medicated shampoo on for 3–5 minutes before rinsing and to use it continuously for at least 2–4 weeks before deciding whether it works.

Why has my head suddenly started itching?

A sudden itchy scalp usually has a new trigger. Think back over the last 1–2 weeks: did you change shampoo, dye, perm or straighten your hair, share a hat or pillow with someone, does your child at school have lice, has the weather turned to the cool season or are you sleeping more in air conditioning, or have you been stressed and sleeping less? Seborrheic dermatitis and psoriasis can flare with stress. If the itch improves within 1–2 weeks after stopping the trigger, there is usually nothing to worry about, but if you have a red swollen rash, weeping, patchy hair loss, or itching for more than 4 weeks, see a dermatologist.

Written by Dr. Patara Voravutinon, Dermatologist · Last reviewed 29 September 2026