A blackhead forms when the opening of a hair follicle (pore) gets plugged with dead skin cells and oil. This blockage causes a bump called a comedo.

When the comedo is open, the clog gets oxidized by the air, turns dark, and becomes a blackhead. If the comedo stays closed, it turns into a whitehead.

Blackheads typically form on your face, but they can also appear on other parts of your body, including your thighs, buttocks, and armpits.

Keep reading to learn why blackheads may appear on your inner thighs and how to treat and prevent them.

Blackhead breakouts on the inner thighs are often the result of a combination of:

  • sweat
  • oil
  • dirt
  • dead skin

Friction and chafing from tight-fitting jeans and leggings can also be contributing factors.

The first steps for preventing and treating your blackheads include:

  • practicing proper hygiene, such as washing your skin regularly with low pH, water-soluble liquid soap
  • exfoliating your skin to remove dead skin cells
  • wearing clean, washed clothing
  • avoiding tight-fitting clothing that rubs against your skin
  • avoiding fabrics that cause perspiration, such as polyester and vinyl

Your healthcare provider or a dermatologist may recommend an over-the-counter topical cream or gel that contains either salicylic acid or retinoids to treat blackheads.

If you have blackheads on your inner thighs and buttocks, they could be a symptom of hidradenitis suppurativa (HS).

HS is a skin condition that tends to affect areas where skin rubs together, including:

  • inner thighs
  • buttocks
  • armpits

Hidradenitis suppurativa symptoms

HS typically presents in areas of your body where the skin rubs together. Symptoms of HS include:

  • Blackheads: These small bumps often appear in pairs and small pitted areas of skin.
  • Small, painful lumps: These lumps are often the size of a pea and appear in areas with hair follicles, sweat, and oil glands, as well as areas where skin rubs together.
  • Tunnels: If you’ve experienced HS for an extended period, tracts that connect the lumps may form under the skin. These tend to heal slowly and may leak pus.

Hidradenitis suppurativa treatment

There’s currently no definitive cure for HS. Your healthcare provider or a dermatologist will determine a course of treatment that may include both medication and surgery.

Medication

The following medications are often used to treat HS:

  • Antibiotic creams: such as gentamicin (Gentak) and clindamycin (Cleocin)
  • Oral antibiotics: such as clindamycin, doxycycline (Doryx), and rifampin (Rifadin)
  • Tumor necrosis inhibitor (TNF) blockers: such as adalimumab (Humira)

Surgery

In some cases, your healthcare provider may recommend a surgical procedure. Surgery for HS may include:

  • Unroofing: This is a procedure in which the skin is cut away to expose the tunnels.
  • Limited unroofing: This procedure, also called punch debridement, is used to remove a single nodule.
  • Electrosurgery: During this procedure, damaged tissue is removed.
  • Laser therapy: This procedure is often done to treat and remove skin lesions.
  • Surgical removal: With this procedure, all affected skin is removed. In many cases, it’s often replaced with a skin graft.

Although you may see blackheads on your face more often, it’s not unusual for them to appear elsewhere on your body, including your inner thighs, buttocks, and armpits.

Treatment and prevention of blackheads on your inner thighs and other areas are similar. They focus on:

  • bathing regularly
  • exfoliating your skin
  • wearing clean clothing
  • avoiding tight-fitting clothing and fabrics that cause perspiration

Blackheads on your buttocks and inner thighs could be a sign of hidradenitis suppurativa.

If you have other symptoms, such as painful, pea-sized lumps or tunnels beneath the skin connecting these lumps, see your healthcare provider or a dermatologist for a diagnosis and treatment plan.