Cystic acne on the back and chest

Why the trunk is harder to treat

Skin on the back is thicker than skin on the face. That is why a benzoyl peroxide wash works best when you leave it on for two to five minutes before you rinse (AAD). A lotion applicator helps you reach the middle of the back.

Anything that rubs can make breakouts flare. A backpack or a tight strap is a common culprit, so the AAD suggests carrying a handheld bag instead, and NIAMS also lists pressure from tight clothes and backpacks. Heavy sweating and humidity are triggers too (MedlinePlus). Shower and change out of sweaty clothes as soon as you can after a workout (AAD).

Gym habits and supplements

Anabolic steroids and whey protein supplements are known risk factors for nodulocystic acne (DermNet), and MedlinePlus lists steroids and testosterone among the things that can trigger acne. If deep lumps started after you began a supplement or a steroid cycle, tell your doctor. For workouts, the AAD suggests loose clothes made of cotton or a fabric that wicks sweat away.

What helps the milder spots around the lumps

These steps calm the smaller pimples; they do not shrink deep lumps.

1. A benzoyl peroxide foaming wash. A 5.3% wash is less likely to irritate or dry your skin, and a 10% wash is the stronger choice (AAD).
2. Adapalene 0.1% gel, a retinoid sold without a prescription since 2016 (FDA), put on after the shower or at bedtime (AAD).
3. Old towels and sheets, because benzoyl peroxide bleaches fabric (AAD).
4. No loofahs, back brushes or scrubs (AAD).
5. An oil-free, non-comedogenic sunscreen with SPF 30 on skin your clothes leave bare, which the AAD says helps clear acne.

If treatment works, you may see results in six to eight weeks, and complete clearing can take three or four months (AAD).

When deep lumps need a dermatologist

Anyone with deep, painful acne on the back needs a dermatologist's help, the AAD says, and so does anyone who sees no change after six to eight weeks of home care. The usual first plan for severe acne is an antibiotic paired with a medicine you apply, with isotretinoin when that is not enough (AAD). A dermatologist can also inject or drain one large, painful lump.

Deep, sore lumps on the back call for the same plan as on the face, and the guide on how to treat cystic acne lays out the steps in order.

Scars on the chest and back

Raised scars favor the trunk. A hypertrophic scar is firm and raised, usually forms on the jawline, chest or back, and tends to appear 1 to 2 months after a breakout clears (AAD). A keloid grows larger than the breakout that caused it (DermNet). Keloids are more common in skin of color, especially along the jawline, chest and upper back (DermNet).

The first sign of a keloid is thickening skin, usually 3 to 12 months after the acne clears. If you notice it, a pressure garment can prevent a keloid or reduce its size (AAD). Starting treatment for deep lumps early means fewer scars.

When it might not be acne

Acne conglobata is a rare, severe form of nodulocystic acne with joined abscesses and nodules on the trunk, limbs and buttocks (DermNet). Lumps found only in skin folds, such as the armpits, groin or under the breasts, point to hidradenitis suppurativa (AAD). Small, itchy bumps that are all the same size on the chest and back can be Malassezia (pityrosporum) folliculitis, a yeast problem rather than acne (DermNet).

Sources

1. Back acne: how to get rid of it. American Academy of Dermatology (AAD).
2. What can clear severe acne? AAD.
3. Acne scars: signs and symptoms. AAD.
4. Nodulocystic acne; Acne scarring; Acne vulgaris; Steroid acne. DermNet.
5. Acne. MedlinePlus, US National Library of Medicine.
6. Acne. National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS).
7. Prescription to nonprescription (Rx to OTC) switch list. US Food and Drug Administration (FDA).

This page is general information, not a diagnosis. See a dermatologist for deep, painful lumps on the back or chest.