Pimples on your breast: causes

This Skinli page has one important distinction in it, so it goes first.

A spot is in the skin. A lump is inside the breast. Those are different problems, and only the first one is a skincare question.

A spot sits on or in the skin. It moves when you move the skin over the tissue beneath, and it changes within days: it comes up, it settles, it goes.

A lump inside the breast feels deeper. It does not move when you move the skin, and it does not come and go over a few days.

The NHS says most breast lumps are harmless, but some can be serious, and that they are often caused by something harmless like a non-cancerous tissue growth or a build-up of fluid. It advises seeing a GP if you notice a lump in your breast or armpit, or any other unusual changes in your breasts, and it names the nipple turning inwards, dimpled skin and bloodstained nipple discharge.

No skincare product addresses any of that. If what you have found is a lump rather than a spot, stop reading and make the appointment. It is a short visit and it settles the question.

The rest of this page is about the skin.

Why chest and breast skin breaks out

Ordinarily, and for ordinary reasons. The skin there has hair follicles and oil glands like skin elsewhere on the body, so acne, blackheads and folliculitis all occur.

The American Academy of Dermatology gives the general rule for folliculitis: it can appear anywhere on the skin, except for our palms and soles. It describes folliculitis as a common skin infection that develops in the hair follicles, and says the infected hair follicles can look like another skin condition, such as acne.

What makes this area more prone than it looks is clothing. The chest spends the day under fabric, often under two layers, frequently with a band or a strap pressing on a fixed line.

The American Academy of Dermatology explains why that matters: when your skin is damp and hot, it is easier to damage your hair follicles and get an infection. A bra band after a warm day is precisely that combination of pressure, warmth and trapped moisture.

So the shape of the breakout is informative. Spots following the line of a band or a strap point to friction and trapped sweat. Spots scattered across the upper chest are more likely ordinary acne, which our guide on chest acne covers in full.

The usual contributors

A bra. Pressure along the band, the strap line and the underwire area, with sweat held under it. A looser fit, a breathable fabric and washing it more often all help. Spots exactly along the band line are the clearest version of this.

Sweat left on the skin. A damp sports top kept on after exercise holds moisture against the skin for an hour or more. Changing soon afterwards and rinsing the area is the controllable part. Our guide on sweat, gym gear and back acne covers it.

Hair products. Conditioner and styling product run down the chest in the shower and rarely get rinsed off. Long hair transfers more during the day. Rinse your chest last, after your hair. Our guide on hair products and back acne explains it.

Heavy creams and sunscreens. Thick products on a large area under clothing can block follicles. Our guide on what non-comedogenic means covers how far the label can be trusted.

The condition worth knowing by name

There is one pattern that is not acne, and it is worth recognising because people treat it as acne for years.

The NHS describes hidradenitis suppurativa as a painful, long-term skin condition that causes skin abscesses and scarring on the skin. It says the lumps develop on the skin in the following areas: around the groin and genitals, in the armpits, on the bottom and around the anus, and below the breasts. It describes a mixture of boil-like lumps, blackheads, cysts, scarring and channels in the skin that leak pus.

The NHS states directly that hidradenitis suppurativa could be mistaken for acne or ingrown hairs, and adds that it is important to recognise and diagnose the condition in its early stages to prevent it getting worse.

Those four areas are exactly where skin rubs on skin. If you get painful lumps that keep returning to the same places under the breast or in the armpit, that heal into scars, and that no acne treatment has touched, this is worth asking a doctor about by name. Our guide on a pimple in the armpit covers the same condition from the other side.

Treating the skin

The ingredients are the same as for the face. The practical difference is area: a wash is often easier than a cream for covering the chest.

Benzoyl peroxide washes are commonly used on the body, and our guide on acne body wash covers the choices. Build up gradually rather than starting daily, because chest skin dries out, and keep using a moisturizer.

Two warnings. Benzoyl peroxide bleaches fabric, so it will mark bras, tops and bedding. And do not scrub the area because it feels bumpy, as that damages the skin barrier and makes everything react more. Our guide on over-exfoliation bumps covers what that looks like.

Our guide on whether you can get a pimple anywhere covers which skin can grow acne and which cannot.

Body acne is usually slower to clear than facial acne, because the skin is thicker and the follicles sit deeper. Give any treatment 8 to 12 weeks before you judge it, which is the same timescale our guide on how long an acne routine takes to work describes.

Why not to squeeze them

The American Academy of Dermatology warns that if you push some of the contents inside the pimple deeper into the skin, which often happens, you increase inflammation. It warns of infection from the bacteria on your hands, and lists permanent acne scars, more noticeable acne and more painful acne among the outcomes.

Chest skin scars readily, and marks there tend to persist. Our guide on cystic back acne covers the deeper lumps that most need leaving alone, and how to fade acne scars and dark marks covers the repair afterwards.

For a deep, sore one, the American Academy of Dermatology advises a clean washcloth soaked in hot water, applied for 10 to 15 minutes, three times daily.

The bumps on the areola that are meant to be there

Worth saying, because people find them and worry.

St Helens and Knowsley Teaching Hospitals NHS Trust describes the anatomy plainly in its breast changes leaflet: the darker area of skin around the nipple is called the areola, and on the areola you may notice there are some small, raised bumps called Montgomery's Tubercles, which produce fluid to moisturise the nipple. It adds that as pregnancy progresses the nipples and areola usually become darker in colour, and the Montgomery's Tubercles may become bigger and more noticeable.

So these are normal anatomy rather than spots. They are not treated, and trying to squeeze or exfoliate them is both pointless and damaging.

Ordinary acne and folliculitis can still occur on the skin around them. What needs a doctor rather than a product is anything bleeding, ulcerated, scaly or crusted, any change in the shape or direction of the nipple, and any discharge.

A painful white dot on the nipple or areola in someone who is breastfeeding is also a separate thing. The same NHS trust leaflet describes a milk blister, or bleb, as usually a painful white dot on the nipple or areola, caused by thickened milk blocking flow near the nipple opening or by skin growing over a duct opening. That is a feeding question for a midwife or a health visitor, and not a spot to treat with acne products.

When to see a doctor

Go sooner rather than later for any lump inside the breast or armpit, any nipple change, any dimpling of the skin, or recurring painful lumps under the breast.

For the acne itself, see a dermatologist if the spots are deep and painful, if they are scarring, or if nothing has changed after three months of consistent treatment.

For the underarm, where the NHS lists the same condition, see a pimple in your armpit, and for the area above see neck acne. Our hub on acne by face area covers each area of the face.

For the skin on your face, the photo check looks at what is there and builds a plan from it. It assesses faces only, and nothing on this page about breast lumps should be put to an app instead of a doctor.