We've probably all experienced itchy armpits after a slipshod or too speedy shaving session (razor burn, anyone?). But what if you haven't trimmed your underarms in weeks (we won't judge - body hair preference is your prerogative), and you still have an intense itch?
Let's face it: Annoyingly itchy armpits can be, well, the pits. But should you be alarmed by this armpit issue? A prolonged prickly feeling in your pits can be caused by a range of things, from minor health issues to more serious medical conditions.
Here, dermatologists dish on the top reasons for unrelentingly itchy underarms, plus ways to find relief.
If you have incessantly itchy armpits, you may be dealing with contact dermatitis, a rash that happens when your skin encounters an irritant or allergen.
"An irritant contact reaction occurs due to something harsh that is aggravating the skin," says Y. Claire Chang, MD, a board-certified dermatologist at Union Square Laser Dermatology. "Common triggers are alcohols, soaps, surfactants, dyes, detergents, resins and even sweat," she says.
Alternatively, "an allergic contact reaction occurs after contact with a substance that you are allergic to," Dr. Chang says. Common culprits include fragrances, preservatives, botanicals, dyes and soaps.
Other symptoms of contact dermatitis may involve, per Dr. Chang:
While anyone can experience this skin issue, "those with eczema, aka atopic dermatitis, may be at higher risk of contact dermatitis," Dr. Chang says.
Your underarm itch could be instigated by intertrigo, an inflammatory rash that is caused by friction, excess moisture and heat along the skin folds, Dr. Chang says.
When these areas of skin rub against each, it leads to irritation. And warm, damp environments only worsen the inflammation, Dr. Chang says. That's because humid places are ideal for the overgrowth of bacteria and/or fungi, which can ramp up the rash, she explains.
In addition to itchiness, intertrigo also presents with red or pink and scaly or dry skin patches, "but the skin can also be moist and macerated, leading to discomfort and burning pain," Dr. Ploch says.
"Sometimes the skin may become cracked, oozy or crusty and may be associated with a bad smell," Dr. Chang adds.
Since intertrigo occurs along skin folds, it can also impact areas such as the groin, under the breasts, between abdominal folds and the buttocks, Dr. Chang says.
And some people may have a greater risk of developing this rash. "Risk factors for intertrigo include immunosuppression, obesity, diabetes, exposure to high heat and humidity and use of a splint, brace or other occluding factors," Dr. Chang says.
Eczema in your armpits? Yep, it can happen.
"Atopic dermatitis, commonly known as eczema, is [an inflammatory skin condition] associated with a red, flaky and very itchy rash, often in the body folds, including armpits, flexural elbows or back of the knees," Dr. Chang says.
On top of the tickly feeling, your armpit "area may become dry or cracked and may bleed if scratched excessively," Dr. Chang says.
Eczema can also be exacerbated when you encounter an allergen, Dr. Ploch says. Which is why atopic dermatitis can at times appear indistinguishable from contact dermatitis.
So, how can you tell the difference? "Contact dermatitis only affects areas that are in contact with an allergen while atopic dermatitis is usually more diffuse [meaning it can affect all areas of your skin]," Dr. Ploch explains.
Though eczema can strike at any age, it's most common in young children, and flares are most frequent in people with dry skin or those who live in low humidity environments, Dr. Chang says.
If your armpits tend to become tender and itchy on hot days or during activities that raise your body temperature, heat rash may be to blame.
"A heat rash can occur due to excess heat and sweat obstructing the sweat glands and ducts, which results in inflammation," Dr. Chang says.
And people usually develop this itchy irritation in skin folds (like armpits) or when clothing rubs against the skin, according to the Mayo Clinic.
In addition to an annoying itch, heat rash may also result in red, prickly and bumpy skin (think: small, uniform bumps), Dr. Chang says. But it can also cause symptoms like small blisters or deep, inflamed lumps depending on severity, per the Mayo Clinic.
"Inverse psoriasis [is an immune-mediated disease that] can cause an itchy, red rash in the skin folds, including the armpits," Dr. Chang says.
This itchy skin issue is initiated by an overreactive immune response that creates inflammation and triggers the overproduction of new skin cells, according to the Cleveland Clinic.
Individuals with inverse psoriasis sprout new skin cells every three to four days (for reference, healthy people grow new ones every month or so), per the Cleveland Clinic. And this exponential increase in skin cells leads to issues like itchiness.
So, what's the difference between psoriasis and inverse psoriasis? "Though typical psoriasis lesions are very thick, white and scaly, inverse psoriasis is often red, non-scaly, sore and itchy," Dr. Chang says.
Also, an inverse psoriasis-related rash appears shinier than a patch of psoriasis plaques, per the Cleveland Clinic. Which is probably because it propagates in parts of the body that tend to be moist (think: not just your armpits, but your belly button, the area below your breasts and your groin too).
A lymphoma - or cancer of the lymphatic system - can also lead to itchy underarms.
"Lymphomas may cause a chronic itch in patients as part of a paraneoplastic syndrome [an abnormal response by your immune system in reaction to a cancerous tumor]," Dr. Chang says.
This appears to happen when antibodies or white blood cells that fight cancer inadvertently attack normal nerve cells, according to the National Institute of Neurological Disorders and Stroke (NINDS). And in this case, it can affect nerves in the skin and trigger itchiness.
"Paraneoplastic itch may or may not present with associated skin changes, including eczema-like or ichthyosiform skin [excessive scaliness] or signs of scratching like excoriations and dyspigmentation," Dr. Chang says. On the other hand, some people simply experience an insistent itch sans other skin symptoms.
Along with itchy skin, other signs of lymphoma may include, per the Mayo Clinic:
"Skin lymphomas like T-cell or B-cell lymphoma [cancers that start in white blood cells that are located in the skin] can also produce rashes that are associated with itch," Dr. Chang says. "The rashes can vary in appearance, ranging from psoriasis-like rashes to generalized redness," she says.
Unfortunately, lymphoma isn't the only malignant medical condition linked to itchy underarms. "Inflammatory breast cancer is a rare form of breast cancer that can be associated with itchiness in the breast and surrounding skin, including the armpits," Dr. Chang says.
As well as itchiness, other signs of inflammatory breast cancer include, per Dr. Chang:
Dr. Chang notes there are a few other - less common - causes of itchy inflmmatory armpit rashes:
"If itchy armpits do not go away with simple at-home measures or get worse, you should see your doctor to get an evaluation [and rule out more serious causes]," Dr. Chang says.
"A board-certified dermatologist may be able to better evaluate and diagnose the condition using visual inspection, biopsy or patch testing," she says.
Once you have a proper diagnosis, your doctor will be able to prescribe an individualized treatment plan and help put an end to your itchy pits.