There are a multitude of factors that lead to underarm discoloration, but the most common cause is skin friction, according to the board-certified dermatologists we talked to. “Constant friction between the skin or with tight clothing can cause hyperpigmentation due to the irritation it causes,” says Mina Amin, MD, a board-certified dermatologist based in Los Angeles. “This condition, called post-inflammatory hyperpigmentation (PIH), is a result of an increase in melanin production as the skin responds to inflammation.”

Another cause can actually be your current underarm care routine. According to Dr. Camp, the deodorant or antiperspirant you’re currently using can lead to irritation or an allergic rash. “A reaction to a deodorant or antiperspirant can cause contact dermatitis, which can result in discoloration,” he says. Another discoloration-inducing tool in your pit regimen is your razor. “Irritation as a result of shaving can cause inflammation in the underarms, which leads to hyperpigmentation as it heals,” says Dr. Camp.

There are also medical conditions, like acanthosis nigricans, which can lead to underarm hyperpigmentation. “This condition can result in dark and thickened skin, typically in body folds such as the armpits, neck, and groin,” says Dr. Amin. “Acanthosis nigricans is often associated with insulin resistance, obesity, and type 2 diabetes. High insulin levels trigger skin cells to reproduce more rapidly, leading to dark thickened plaques.”

Good news: There are quite a few over-the-counter avenues you can take to improve your pits’ skin tone. “Several skin-care ingredients can help reduce underarm hyperpigmentation by lightening dark patches and promoting even skin tone,” says Dr. Amin. The best armpit brightening cream will contain retinol or exfoliating acids, such as glycolic, salicylic, and lactic acids, for their brightening properties.

“Regular exfoliation combined with brightening agents can help improve the appearance of underarm hyperpigmentation over time,” she says. However, when using active ingredients like exfoliating acids and retinol, Dr. Amin says it’s important to introduce them gradually and, if you’re exposing skin during daylight hours, always follow up with sunscreen, as they can increase photosensitivity.

In short, no. But, depending on the root cause of your darkened underarms, you can make changes that keep your skin looking brighter in the long term. Namely, if friction or shaving make your pits’ pigmentation worse, you can use products that prevent chafing or shave less frequently (or even opt for laser hair removal instead). “While discoloration can often be improved substantially, maintenance treatment is usually required,” Dr. Luftman says. “If the underlying cause continues, pigmentation often returns over time.” So, in most cases, you’ll need to continue using brightening products in order to sustain your results.

In-office treatments for dark underarms (and not one of the medical conditions we mentioned above) include prescription-strength topicals—which usually contain hydroquinone or retinoids—as well as chemical peels, and laser or pulse light sessions, says Dr. Luftman. Ultimately, your derm will need to diagnose the underlying cause of your pigmentation before determining which treatment is best for you. “Because the underarm skin is thin and sensitive, professional evaluation helps minimize the risk of irritation or worsening pigmentation,” Dr. Luftman explains.

• Mina Amin, MD, a board-certified dermatologist based in Los Angeles
• Debra Luftman, MD, a board-certified dermatologist based in Beverly Hills and Calabasas, California
• Nazanin Saedi, MD, a board-certified dermatologist based in East Norriton, PA
• Sarah Sung, MD, a board-certified dermatologist based in Seattle

When Allure tests a product, our editors look at it from every angle in an effort to best serve you. We review ingredients, scrutinize brand claims, and, when necessary, examine peer-reviewed scientific and medical studies. In addition to testing each and every product that’s included in each and every review, we rely on experts who shape their fields, including dermatology, cosmetic chemistry, and medicine, to help us vet the ingredients and formulas.

For our list of the best armpit brightening creams, we considered each product’s performance across five primary categories: product ingredients and efficacy, packaging, fragrance, texture, and product wear. Every product was determined to have excelled in each category by our editorial team, which is composed of in-house writers and editors as well as contributors—along with special consideration from board-certified dermatologists. To learn more information on our reporting and testing processes, read our complete reviews process and methodology page.

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