20 Reasons for Your Itchy Scalp (Besides Head Lice)
A little itch is nothing to be concerned about, but if you
can't stop scratching your head, here are some causes of an itchy scalp.
The itching is a symptom, not a condition
There it is again—that tingling feeling up top. How good
would it feel to just reach up and rake your fingernails across that scalp of
yours a few times? But you don’t dare because once you start, it’s so hard to
stop. As Harvard-trained dermatologist, Khalil A. Khatri, MD admits, “Once you
get into the “itch-scratch-itch cycle, it’s difficult to get out of it.” It’s
vexing when your head itches not only because it’s so hard not to scratch, but
also because it’s usually a symptom of something else. So what does it mean
when your head itches? Fear not. There are many reasons for your itchy scalp,
we were assured by Dana R. Brewer, PA, a physician’s assistant with a specialty
in dermatology, and most of them are a cinch to treat. And if your hair is
thinning, breaking or feeling brittle here are 8 other things your hair is
trying to tell you about your health.
Lice
OK, let’s just get this one out of the way. Let’s say you’ve
got school-age kids, and you find yourself asking, “Why does my scalp itch?” Is
there any way you’re not going to wonder if it’s head lice? Head lice are tiny
bugs that attach themselves to body hair, according to the Centers for Disease
Control and Prevention. “Head lice can be seen in the form of eggs, aka nits,
along the hair shaft,” explains Rhonda Q. Klein, MD, an associate clinical
professor of dermatology at Yale-New Haven Hospital and West Haven VA Medical
Center. Although the nits can be confused with dandruff, when you see adult
lice moving around your head, that’s unmistakable. “You can use physical
methods to remove the lice,” Dr. Klein says, “and you can try natural lice
shampoos and natural lice removers, “although what you’ll probably end up
needing to eradicate a lice infestation is an actual “insecticide like
pyrethrin and permethrin,” depending on resistance patterns in your area.
“Shaving the head is also an easy solution for boys.” Make sure you know how to
spot the difference between dandruff and lice.
Scabies
If it’s not lice, you might wish it were when you learn
about scabies, which according to Dr. Khatri can cause itching not just on the
scalp but also on the entire body. Scabies on the scalp isn’t common, and it
usually affects those with compromised immune systems.
Scabies are an infestation of the “human itch mite” (aka
sarcoptes scabiei var. hominis). The scabies mites burrow into the upper layer
of the skin, where they live and deposit their eggs, according to the CDC. The
microscopic scabies mite almost always gets passed along by direct, prolonged,
skin-to-skin contact with a person who already is infested. Scabies in adults
frequently is sexually acquired, although it can also be spread without sexual
contact in crowded conditions, including households, nursing homes,
extended-care facilities, child-care facilities, and prisons.
Dandruff
So, let’s say you’ve ruled out head lice and scabies. If
you’re still asking “why does my scalp itch,” then dandruff is your most likely
culprit. Or more specifically, seborrheic dermatitis, which is considered a
severe form of dandruff caused by an overreaction the body has to normal yeast
that lives on the skin, according to Jennifer Haley, MD, a board-certified
dermatologist based in Scottsdale, Arizona. Dandruff affects about 40 percent
of people and tends to come and go during one’s lifetime. “Weather changes,
stress, and increased sugar in the diet can bring it out.”
Over-the-counter remedies include products containing the
active ingredient, salicylic acid (such as Neutrogena T/Sal Shampoo) and
products containing antifungals such as ketoconazole or selenium sulfide
(Selsun Blue Shampoo contains the latter). Natural remedies for dandruff
include tea tree oil. And a product called Scalpicin can help decrease itching,
Dr. Haley advises. If over-the-counter remedies do not resolve the issue, then
see a board-certified dermatologist, who can not only prescribe steroidal
anti-inflammatories but also determine if some other condition is causing your
itchy scalp symptoms.
Allergic reaction
If you recently colored your hair, it’s possible that you’re
experiencing an allergy to the dye. This is true even if you’ve used the
product before without incident. “If the hair color is temporary or
semi-permanent it can be washed out,” explains Joshua Zeichner, MD, a
board-certified dermatologist and director of Cosmetic and Clinical Research at
Mount Sinai Hospital in New York City, “but if it’s a permanent dye, that
presents a more challenging situation, although there are products on the
market that can remove permanent dye altogether.”
“People can have a reaction to anything they put on their
scalp—from shampoo to hair dye to Rogaine,” points out Dr. Haley. “And don’t
forget about those hair-smoothing keratin treatments, adds Dr. Klein.
To pinpoint the culprit product or ingredient suggests
Tsippora Shainhouse MD, a board-certified dermatologist in Beverly Hills and
Clinical Instructor at the University of Southern California, try using one
product at a time for a week at a time, rather than combining many at the same
time.” And then while your scalp is healing, choose only gentle and sensitive
skin formulations.
Psoriasis or eczema
An itchy scalp can also be caused by inflammatory skin
conditions such as eczema (aka atopic dermatitis, especially in babies, eczema
can present on the scalp) and psoriasis (which is more likely to appear on the
scalp of an adult). Dr. Zeichner says explains that these conditions arise when
your immune system gets “angry” at your skin, leading to red, flaky, itchy
patches.
Psoriasis looks similar to dandruff but is usually thicker
and red, notes Esta Kronberg, MD, a dermatologist in Houston, Texas, but it can
be treated the same way dandruff is treated. For both eczema and psoriasis, Dr.
Klein recommends topical steroids, vitamin D analogues (calcipotriene), coal
tar, salicylic acid, excimer laser, phototherapy, and immunomodulatory agents
for severe cases. For more relief, try one of these all-natural psoriasis and
eczema treatments.
Sunburn
It’s possible that your itchy scalp is nothing more than a
sunburn, Dr. Shainhouse suggests. If you’ve been out all day and forgot to wear
a hat, think sunburn first, and get some relief with a cool shower and some
hydrocortisone cream (available over the counter).
Dry scalp
The winter months can come with dry air, whether cold
outdoor air or heated indoor air. The dryness strips the scalp of its
protective oils, according to Dr. Shainhouse, who suggests that if your head
becomes itchy in winter, your first plan of action could be to try a
moisturizing hair conditioner or a once-per-week scalp and hair mask.
Dirt and sweat
“When you don’t wash your hair often enough, natural oils,
dirt, and product residue build up on your roots and scalp, causing you to itch
and scratch,” says Dr. Shainhouse. ” Scalp skin is similar to face skin and
need to be washed.” Dr. Shainhouse recommends washing every other day. If you
think your strands are too dry for frequent washing, flip your head into the
sink and focus on the roots only. Scrub your scalp and roots with shampoo and
be sure that it lathers well before rinsing in order to dissolve the excess
oils and debris.
Likewise, your scalp could itch because you simply skipped
your shower after a “super-soaker spin class,” Dr. Shainhouse suggests. “When
the sweat on your scalp dries, it can irritate the skin, leaving it feeling
itchy.” The simple solution: Wash your hair every time you sweat/work out.
Rosacea
Rosacea classically presents as red flush and (sometimes)
pimples on the face. Rosacea may flare in the heat, after eating spicy, hot, or
caffeinated foods and drinks, or as a result of emotional stress, according to
the American Academy of Dermatology. While it normally affects the cheeks,
chin, and nose, says Dr. Shainhouse, it can potentially affect the scalp,
causing an itchy or burning or stinging sensation. If you think that you might
have rosacea, see your dermatologist to figure out the best management plan.
Folliculitis
If your itchy scalp is accompanied by what looks like red
pimples—with a hair in the center of each one—you may be looking at a case of
folliculitis, according to Dr. Khatri. The pimples may have pus in them, and
they may itch or burn. When the pimples break open, they may drain pus, blood,
or both.
Most of the time, the symptoms disappear on their own within
a week to 10 days. Topically, you can use an antibacterial cleanser, Dr.
Kronberg suggests, but if it doesn’t seem to be clearing on its own, you may
need a course of oral antibiotics. Folliculitis is just one of the many skin
conditions that look like acne.
Fungus and ringworm
A fungal infection (not the same one that causes dandruff)
can cause an itchy scalp as well, says Dr. Haley, although this is more common
in children. It’s also called ringworm, or tinea capitis. A fungal infection
can be caused by moisture remaining on the scalp for extended periods, says Dr.
Kronberg. If you have one, you’ll know soon enough because it won’t respond to
anything except oral antifungals, which only your doctor can prescribe.
A too-tight ponytail
Like ringworm, wearing a ponytail can cause both hair loss
and scalp itching. “Wearing your hair up all day, or in overly tight or heavy
hairstyles such as braids, buns, extensions, and weaves, can tug on the hair
follicles, causing stress and scarring over time, leading to hair thinning and
hair loss,” Dr. Shainhouse says. “However, this styling also pulls the hairs
and surrounding nerves and muscles in an unnatural direction, leaving your
scalp sore and sometimes itchy when you let your hair down.” Dr. Shainhouse’s
simple solution? Stick to looser styles, keep hair in tighter styles only for
short periods, and vary your hairstyles throughout the week.
Alopecia areata
Another cause of both scalp-itch and hair loss is alopecia
areata. Dr. Zeichner explains alopecia areata as a condition where your immune
system “gets angry at your hair, producing cells that attack it.” Patients may
develop small bald spots, or in severe cases, experience complete hair loss.
One of the earliest signs of alopecia areata is itching of the scalp. So, Dr.
Zeichner suggests that if your scalp itching is accompanied by hair loss that
can’t be explained by ringworm or an up-do (aka traction alopecia), make sure
to visit a board-certified dermatologist for evaluation.
Lichen planopilaris
A far more rare cause of itching plus hair loss is Lichen
planopilaris, according to Dr. Haley. Lichen planopilaris is a rare
inflammatory condition that results in patchy progressive permanent hair loss
mainly on the scalp. According to the American Skin Association, this condition
affects around one percent of Americans, most of whom are over age 30. The aim
of treatment is to slow the progression of the inflammatory process, which
includes slowing the loss of hair.
Sarcoidosis
Another unusual reason for scalp itchiness is sarcoidosis,
according to Dr. Klein. Sarcoidosis is the growth of tiny collections of
inflammatory cells (granulomas) in different parts of your body. Doctors
believe sarcoidosis results from the body’s immune system responding to an
unknown substance, most likely something inhaled from the air. Someone with an
itchy scalp should not assume they have sarcoidosis, however, unless other
symptoms are present, including:
- Fatigue
- Fever
- Swollen lymph nodes
- Weight loss
- Persistent dry cough
- Shortness of breath
- Wheezing
- Chest pain
- A rash of red or reddish-purple bumps, usually located on the shins or ankles, which may be warm and tender to the touch
- Disfiguring sores (lesions) on the nose, cheeks, and ears
- Areas of skin that are darker or lighter in color
- Blurred vision
- Sensitivity to light
- Phantom scalp itch
In rare cases, an itchy scalp has no organic cause at all,
which is to say, it is accompanied by no other objective medical findings, Dr.
Klein explains. This is known as scalp dysesthesia. It is often triggered or
exacerbated by a psychologic or physical stressor and may be a manifestation of
an underlying psychiatric issue or chronic pain syndrome. It is usually seen in
elderly patients, and the key treatment is low-dose antidepressants, which Dr.
Klein says can be life-changing for patients.
Cervical spine disease
Oddly enough, an itchy scalp that has no other cause could
be a sign of cervical spine disease, which may be visible by imaging, says Dr.
Klein. The mechanism here is thought to be related to chronic tension and nerve
impingement. Treatment may include gabapentin (a drug used for nerve pain that
also may be helpful in treating menopause-related symptoms), botox injection,
and epidural injections.
Lupus
Lupus is a serious autoimmune disease that can present with
itching as well as dry scalp, says Dr. Haley, but it also involves many other
symptoms, which may include arthritis, photosensitivity, oral and cutaneous
ulcers, and joint pains. A skin biopsy can be helpful in ruling out Lupus.
Lymphoma
In very rare cases, an itchy scalp can be a sign of
lymphoma, Dr. Haley says, specifically, a form called “Cutaneous T-Cell
Lymphoma.” The itching with this form of lymphoma tends to be severe and is
usually accompanied by a rash and enlarged lymph nodes. It affects more men
than women and tends to appear after the age of 50. A skin biopsy will be
helpful in diagnosis, as well as blood testing.
Skin cancer
Also very rarely, scalp itching will be caused by the
presence of a skin cancer lesion, according to Dr. Khatri. In particular,
melanoma can cause itching, but so can other forms of skin cancer. If your
scalp is itchy, it’s a good idea to have someone take a look to see if there
are any bumps or sores. Anything that is causing severe discomfort or that doesn’t
resolve on its own within two weeks should be checked by a doctor.