In February 2026, beauty editor Ariana Yaptangco developed underarm dermatitis and chronic eczema from using an old razor and expired deodorant. Medical experts warn that improper shaving routines, expired products, and lingering monsoon humidity can trigger rashes, infections, and skin barrier damage.
Maintaining a body care regimen often involves treating the face and limbs to premium products while treating underarms as an afterthought. A quick shave, a swipe of deodorant, and an exit out the door make up a routine that many follow without a second thought. But neglecting that delicate skin can backfire.
For Ariana Yaptangco, a quick and rough shave paired with an old razor and expired deodorant in February 2026 brought itching, inflammation, and a rough texture. What started as irritation turned into a case of underarm dermatitis, demonstrating how neglected underarm habits can lead to skin trouble.
Understanding Underarm Dermatitis: Irritants and Allergens
Dermatitis is a broad term for skin inflammation, and the underarms are particularly vulnerable to contact dermatitis. According to medical specialists, this condition generally splits into two categories: irritant dermatitis and allergic dermatitis.
“Irritant dermatitis comes from a substance touching your skin, which is causing an irritant reaction, or a rash.”
Dr. Chelsea Hoffman, MD, Hudson Dermatology and Laser Surgery
Applying active ingredients such as retinoids to treat underarm pigment can trigger irritant reactions, though even sweat alone can be irritating to people. While irritant dermatitis appears quickly, allergic contact dermatitis involves a delayed immune response to environmental triggers. Additives like preservatives or fragrances found in deodorants rank among the most common causes.
Left untreated for a few months, Yaptangco’s initial reaction evolved into atopic dermatitis, also known as chronic eczema. The neglected rash left her skin thick, scaly, and marked by leathery lines due to dryness alongside dark discoloration.
The Hidden Risks of Shaving and Expired Products
Shaving remains a primary mechanical stressor for underarm skin. Because the blade takes off the top of the skin, using a dull, dirty, or old razor increases the risk of barrier damage and subsequent infection.
“Shaving basically kind of takes off the top of your skin.”
Dr. Chelsea Hoffman, MD, Hudson Dermatology and Laser Surgery
Lauren Lovelady, founder of the body care brand Each & Every, notes that armpit skin is delicate and vulnerable, especially during the summertime. People tend to put a little bit more stress on the area through shaving and applying products without providing adequate hydration.
Beyond mechanical friction, environmental factors compound daily wear and tear. In hot, humid conditions, sweat takes longer to dry, creating a breeding ground for microorganisms.
Monsoon Humidity and Fungal Complications
Climate and seasonal shifts introduce additional skin hurdles. During rainy or humid seasons, trapped moisture and friction challenge the skin barrier, creating conditions for bacteria and fungi.
Dr. Nirupama Parwanda, a dermatologist and founder of Zolie Skin Clinic, points out that monsoon humidity keeps skin damp for longer, which fosters fungal infections while sweat and blocked pores trigger acne and eczema flare-ups.
Conditions like ringworm, jock itch, athlete’s foot, and candidal intertrigo thrive in warm, moist areas such as the armpits, groin, and spaces between fingers and toes. Persistent itching, redness, or round-shaped rashes in these areas require professional evaluation rather than casual dismissal as temporary monsoon irritation.
Pathogens, Treatment, and Proper Barrier Care
When armpits remain moist for extended periods, pathogens beyond standard dermatitis can take hold. Yeast and other microbiome elements thrive in those environments, making rare fungal infections a possibility.
Healing underarm dermatitis requires patience. Treatment protocols mandate minimizing shaving or waxing to protect the compromised skin barrier. Specialists advise patients to avoid anything that’s going to compromise the barrier.
Recovery often involves prescribed topical steroids to bring down inflammation, paired with lightweight, fragrance-free moisturizers. Experts suggest looking for products with ceramides or lactic acids to keep skin moisturized. Experts also caution against relying on combination creams containing topical steroids, which can temporarily suppress redness and itching while allowing underlying fungal infections to worsen.
