7 minute read

Bacne: Causes and How to Treat It

Written by
Reviewed by
Dr Ai Nhi Bui

Back acne, commonly referred to as bacne, is both common and treatable. It may flare up suddenly, or you may have noticed it slowly worsening. In either case, learning what causes back acne and how to treat it is the first step to clearer skin. Whether the pimples on your back are mild or severe, getting appropriate treatment will help you avoid scarring and skin damage.

Although it may appear that life would be easier without sebaceous glands, sebum is essential for keeping your skin and hair supple and waterproof. When these glands get clogged with sebum, dead skin cells, and bacteria, you can get back acne. Sweating and friction only compound the problem.

Because the pores on your back are deep, treatment may take a little longer than you would like, but this guide will walk you through the causes of back acne and how to treat it, putting you back on track to clear skin.

What Causes Back Acne?

Overactive oil glands, excess dead skin cells, a proliferation of acne-causing bacteria, and skin trauma cause back acne.

Overactive oil glands

At the start of puberty, both men and women produce more androgens or male sex hormones. Androgens cause the sebaceous glands to produce sebum. If your sebaceous glands are overly sensitive to androgens, they make too much sebum resulting in clogged glands and acne on your back.  

The severity of back acne is proportional to the rate of sebum production and the structure of the hair follicle canal. If the hair follicle canal is narrow and sebum production is high, you can see how easy it would be for the duct to become clogged.

Excess dead skin cells

Every day, millions of skin cells are shed. Sebum transports dead skin cells to the surface, where they flake off. If sebum carries dead skin cells along the sebaceous duct to the inside of the hair follicle, the hair follicle's exit route can become blocked and clogged with sticky skin cells. Dead skin cells and keratin (a protein found in the skin, hair, and nails) can clump together with sebum, causing bacne.

Acne-causing bacteria

Cutibacterium acnes (previously called Propionibacterium acnes) colonise the skin and become trapped in the clogged sebaceous duct. Enzymes secreted by the bacteria stimulate inflammation. White blood cells and other immune cells leave the bloodstream and enter the tissue surrounding the inflamed sebaceous gland and hair follicle, causing irritation, swelling and pain.

Showering after exercise and using gentle cleansers can help reduce the number of acne-causing bacteria and loosen trapped skin flakes and sebum.


Pressure, friction, and heat can all irritate bacne. Friction from sports equipment, backpacks, and exercising in hot weather, especially if not followed by a shower, may all play a role in worsening back pimples. Avoid wearing tight-fitting exercise clothing that traps sweat and rubs on the skin.

How serious is your bacne?

The severity of back acne ranges from mild to severe. Early treatment can keep your back acne from worsening. Noninflammatory acne is due to increased sebum production, which leads to larger pores, blackheads, and whiteheads. Noninflammatory acne is seen in less severe forms of back acne.


Whiteheads are closed comedones (acne) that appear as small, white, or flesh-coloured bumps. The pores are clogged with dead skin cells and sebum, a natural oil produced by the sebaceous glands. Since a whitehead's content is not open to the air, the pigment melanin does not become oxidised and maintains its white colour.


Blackheads are open comedones. The contents of a blackhead are open to the air. Melanin, a pigment found inside hair follicles, becomes oxidised by the air and turns the contents of the comedones black.

Inflammatory acne occurs when oil, dead skin cells, and bacteria build up in sebaceous glands. As your immune system fights the infection, the area can become inflamed. Deep in the tissue, nodules and cysts can form. Nodules and cysts characterise more serious forms of back acne and can be harder to treat.


Papules are small, raised bumps on the skin that have become inflamed. Inflammation causes redness, swelling, heat, and pain.


Pustules are papules that are filled with pus. A pustule is filled with white, yellow, or cream-coloured pus. It has a white top, and a pinpoint opening may be seen.


Nodules are deeper and larger than pustules and papules. Infected debris from the sebaceous gland spreads throughout the dermis (deeper layer of the skin), causing inflammation and swelling. Nodules may involve more than one sebaceous gland.


Cysts are deeper and larger lesions that are filled with pus and are painful. Cystic bacne can lead to scarring.

Now that you know what causes back acne, the next step is to learn how to treat it.

Treatment for Back Acne

Pimples on your back can be a challenge to treat. Back skin is thicker, so clogged sebaceous glands are often deep and harder for creams to access. Not to mention how hard it is to apply medication to the back! Lotion applicators designed for treating back acne are a huge help.

Mild back acne

When you only have whiteheads and blackheads, your back acne is considered mild. Mild acne can be treated initially with a single agent such as salicylic acid, topical retinoids like tretinoin, or benzoyl peroxide. If there is no improvement in six weeks or so, topical or oral antibiotics may be added to your treatment plan. A maintenance therapy to treat your back acne can be either a combination of topical retinoids and benzoyl peroxide or benzoyl peroxide and a topical or oral antibiotic.

Since back skin is thicker than facial skin, you may need to leave your benzoyl peroxide on longer so it can fully penetrate your skin. Wear an old shirt to keep benzoyl peroxide from bleaching clothes, sheets and towels.

Moderate back acne

Moderate back acne is a step up in severity. In addition to whiteheads and blackheads, you may also have inflammatory pustules and papules. Topical treatments are usually used for moderate acne as well. Typically, benzoyl peroxide is combined with either an antibiotic ointment or a topical retinoid. Using hormonal therapy, such as taking the birth control pill, instead of or in addition to topical treatments is an alternative treatment option for moderate back acne in females.

Severe back acne

You have many comedones, pustules, and papules if your back acne is moderate to severe. There could also be a few nodules or cystic bacne. Severe acne is distinguished by the presence of numerous nodules and cysts. Acne that is severe or difficult to treat can result in permanent scarring. Scarring can be reduced with early and effective treatment.

Moderate to severe acne may be treated with all three choices of topical treatment: a topical or oral antibiotic, benzoyl peroxide, and a topical retinoid. If there is scarring or your acne is not improving, you will probably be referred to a dermatologist to see if you are a suitable candidate for systemic retinoids.

Acne normally clears up by the mid-20s, although this is not always the case. At age 40, 1% of men and 5% of women still have occasional acne breakouts. Some women will develop acne for the first time in their mid to late 20s. Many people have acne on their back. Talking to a doctor as soon as possible is the best way to explore the range of treatment options available for back acne.

Acne treatment online with Rosemary Health

Whether on your face, neck or back, acne can be challenging to deal with, but it can easily be evaluated and treated through Rosemary's online network of doctors and pharmacists. No more waiting rooms or going to the pharmacy. Start your online acne visit today and get the best treatment for your back acne.


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