Why do my armpits smell even after washing?

Residual bacteria and a build-up of dead skin on the surface continue producing odour even after washing — regular gentle exfoliation helps remove that build-up at the source.

How do you get rid of dark underarms?

Consistent use of a gentle exfoliating acid like glycolic acid, combined with sun protection and avoiding harsh hair-removal irritation, is the most effective non-prescription approach to fading dark underarms over several weeks.

Can I use glycolic acid on underarms every day?

Once your skin has built tolerance, yes — the Body Stick is designed for daily use on areas like underarms. Start slower and build up.

Will it help with ingrown hairs too?

Yes. Glycolic acid helps clear the follicle of the dead skin and debris that commonly causes hair to curl back under the skin.

Can I use both the Body Stick and the Toner?

You can, but don't layer them on the same area in the same routine — pick one for your underarm routine to avoid over-exfoliating this sensitive area.

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Glycolic Acid Underarm Treatment: The Gentle Fix for Dark, Bumpy or Smelly Armpits

Dark, bumpy or smelly underarms? Here's how glycolic acid gently exfoliates, fades discolouration and fights odour at the source.

Author

askINKEY skincare advisor

Published

11 October, 2026

Time to read

4 minutes

Underarms go through a lot. Deodorant, antiperspirant, friction from clothing, regular hair removal — it's one of the most sensitive, high-maintenance areas of skin on the body, yet it rarely gets the same skincare attention as your face. The result? Many of us end up dealing with dark underarms, rough or bumpy texture, ingrown hairs, or a lingering odour that no antiperspirant seems to fully fix.

The good news: there's a simple, dermatologist-backed ingredient that can help with nearly all of it — glycolic acid.

Why Do My Armpits Smell, Look Dark, or Feel Bumpy?

Quick answer: Underarm odour, darkness and bumpy texture are usually caused by a build-up of dead skin and bacteria, friction from shaving or waxing, and blocked hair follicles — all of which respond well to gentle exfoliation.

Build-up of dead skin cells — underarms don't exfoliate naturally the way facial skin might with your regular routine, so dead skin, product residue and sweat can accumulate, leading to dullness and discolouration.
Friction and hair removal — shaving, waxing or epilating can cause micro-irritation, ingrown hairs, and post-inflammatory hyperpigmentation (dark marks left behind after irritation).
Bacteria and sweat — underarm odour isn't caused by sweat itself, but by bacteria breaking down sweat on the skin's surface. Built-up dead skin gives bacteria more to feed on.
Keratosis pilaris (KP) — the same "chicken skin" bumps that show up on arms and thighs can appear in the underarm area, caused by keratin blocking hair follicles.

How to Remove Dark Marks from Underarms

Quick answer: Consistent gentle exfoliation with glycolic acid is one of the most effective ways to fade dark underarm marks, as it speeds up cell turnover and clears the pigmented dead skin sitting on the surface.

Glycolic acid is an AHA (alpha hydroxy acid) with the smallest molecular size of the group, meaning it penetrates effectively to dissolve the "glue" holding dead skin cells together. For underarms specifically, this means:

Smoother texture — regular gentle exfoliation helps prevent and reduce bumpy, rough skin
Reduced discolouration — removing built-up dead skin and encouraging cell turnover visibly fades dark marks over time
Fewer ingrown hairs — keeping follicles clear of debris helps hair grow through properly instead of curling back under the skin
Better odour control — less dead skin and buildup means less for odour-causing bacteria to feed on

Two Ways to Use Glycolic Acid on Your Underarms

1. Glycolic Acid Exfoliating Body Stick — €17.00 / 45g

Formulated with 7% Glycolic Acid, 0.5% Salicylic Acid and 10% Shea Butter, this solid stick is the most targeted, mess-free way to treat underarms. Glide it directly onto clean, dry skin — no rinsing, no residue. Visible results in as little as 28 days.

How to use: Apply once daily to clean, dry underarms. Wait 10–15 minutes before deodorant. If you've just shaved, waxed or epilated, wait at least 8 hours first.

2. Glycolic Acid Toner — €14.00 / 100ml

A stronger 10% Glycolic Acid formula with 5% Witch Hazel to help control oil and calm skin. Sweep over underarms with a cotton pad as a lighter-weight alternative to the stick.

How to use: PM only. Start 1–3x per week on clean, dry underarms with a cotton pad, building up gradually. Avoid within 8 hours of hair removal, and don't layer with other acids, retinol or vitamin C on the same area.

The 8-Hour Rule: Why It Matters

Quick answer: Always wait at least 8 hours after shaving, waxing or epilating before applying glycolic acid to underarms, since freshly exposed skin has micro-abrasions that are more prone to irritation from acids.

How Often Should You Exfoliate Your Underarms?

Underarm skin is thinner and more reactive than skin on arms or legs, so less is more:

Beginners: 2–3x per week with the Body Stick, or 1–3x per week PM with the Toner
Once tolerated: many people move up to once daily with the Body Stick
Always patch test a new product first, and stop if you notice persistent redness or stinging

Free standard delivery on EU orders over €55.

Frequently Asked Questions

Residual bacteria and a build-up of dead skin on the surface continue producing odour even after washing — regular gentle exfoliation helps remove that build-up at the source.
Consistent use of a gentle exfoliating acid like glycolic acid, combined with sun protection and avoiding harsh hair-removal irritation, is the most effective non-prescription approach to fading dark underarms over several weeks.
Once your skin has built tolerance, yes — the Body Stick is designed for daily use on areas like underarms. Start slower and build up.
Yes. Glycolic acid helps clear the follicle of the dead skin and debris that commonly causes hair to curl back under the skin.
You can, but don't layer them on the same area in the same routine — pick one for your underarm routine to avoid over-exfoliating this sensitive area.

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