Acne can manifest in various areas of the body, not just the face. However, some bumps that appear in places like the armpits, scalp, or buttocks may not actually be acne, according to board-certified dermatologist Dr. Christina Marcelus. The treatment for these "acne-like" blemishes often depends on identifying their true cause.
Bikini Line Breakouts
Small bumps on the bikini line after hair removal are frequently ingrown hairs, not pimples. Dr. Marcelus explains that shaving, waxing, and epilating can traumatize hair follicles, causing the hair to curl back into the skin. Tight synthetic underwear and prolonged wear of damp workout clothes can exacerbate this by trapping heat and friction. To address this, it is recommended to change out of wet clothing promptly after exercise and to use a body wash or pads containing salicylic acid, which helps target follicular plugging and ingrown hairs. Products with salicylic acid, glycolic acid, and witch hazel are suggested for post-hair removal irritation.
Scalp Pimples
While the scalp does have oil glands and can develop acne, many bumps are actually folliculitis, an inflammation or infection of the hair follicles, or are caused by yeast rather than bacteria. Overuse of heavy hair products, dry shampoo, and sweating under hats can aggravate these bumps. For suspected yeast-related scalp issues, Dr. Marcelus recommends shampoos containing ketoconazole or zinc pyrithione, which should be left on the scalp for a few minutes before rinsing.
Buttocks Blemishes
Red bumps on the buttocks are typically folliculitis, often caused by mechanical issues like prolonged sitting on compressed, occlusive, or damp fabric. This can be triggered by sitting in sweaty leggings or a wet swimsuit. Folliculitis can be bacterial or yeast-based. For bacterial folliculitis, a chlorhexidine wash can be effective. Some butt bumps may also be keratosis pilaris, a condition caused by keratin buildup that clogs hair follicles. Lotions containing urea or lactic acid can help improve the rough texture associated with this condition.
Armpit Irritation
True acne is rare in the armpits due to a lack of the oil-producing follicles required for acne formation. Bumps in this area are more commonly caused by irritation from shaving or folliculitis. Harsh ingredients in deodorants or antiperspirants can also lead to acne-like reactions. Dr. Marcelus also points to hidradenitis suppurativa, a chronic inflammatory condition affecting blocked hair follicles, as a possibility. This condition can cause recurring painful lumps in the armpits, groin, under the breasts, or between the buttocks, which may drain or leave scars. Unlike acne, it is not contagious and not related to hygiene, and there are FDA-approved treatments available. Individuals suspecting hidradenitis suppurativa should seek medical attention.
Lifestyle Adjustments
Several lifestyle changes can help manage breakouts in sensitive areas. These include changing out of wet clothes immediately after workouts, opting for breathable fabrics over tight synthetics, avoiding excessive scrubbing of inflamed areas, showering after sweating, and not sitting in wet swimwear. When shaving, it is advised to shave with the grain using a fresh blade and to avoid multi-blade razors. Additionally, Dr. Marcelus cautions against applying full-strength facial acne products to skin folds, as concentrations that are tolerable on the face can cause painful irritant dermatitis in areas like the groin or armpits.