Hair grows straight up and out from the skin, but occasionally, a strand of hair curves and grows back into the hair follicle rather than breaking through the skin. Known as ingrown hairs, these are more likely to occur after shaving or tweezing.

Ingrown hairs in the armpit can be uncomfortable or itchy, but they often clear up on their own without needing to see a doctor. Here’s some background on managing ingrown hairs in this common area, including some reasons why they might occur.

Causes of Ingrown Hairs

Ingrown hairs can show up anywhere on the body, but they’re more likely to happen in places where you remove hair. As hair regrows, it may turn inward and not make its way out of the skin right away. This process leads to an inflamed bump that’s slightly raised, discolored, and irritated. People with curly or coarse hair are more prone to getting ingrown hairs.

Prevention Tips

Because shaving, waxing, and tweezing raise the risk of ingrown hairs, letting the hair grow out can help. You can also try different hair removal methods, such as trimming the hair short with an electric trimmer or using a depilatory cream that dissolves the hair on the surface of your skin.

Sometimes, taking extra precautions, such as shaving in the direction of hair growth, can prevent ingrown hairs. Be sure to wet your underarms with warm water before shaving. Always use shaving cream to reduce friction. A single-blade razor that’s rinsed after each stroke is less likely to cause irritation and ingrown hairs. Finally, don’t use an old blade. Change your razor regularly or buy single-use disposable razors.

Common Symptoms

Ingrown hairs produce small bumps with or without pustules (small pus-filled pimples). They’re sensitive and can hurt or itch. The raised bump may be more noticeable if it’s a different shade than your general skin tone, such as red or pink on lighter skin or black or purple on darker skin. Ingrown hairs usually affect a single hair follicle, so the bump is small and isolated. However, it’s possible to have more than one ingrown hair at a time.

Treatment Options

Typically, ingrown hairs can be treated at home — that is, if they require treatment at all. After a week or two, most ingrown hairs grow out naturally. Exfoliating the area with a scrub or warm washcloth can speed up the healing process. You can also place a warm compress over the ingrown hair for 15 seconds to help release the blockage. Resist the urge to pick or scratch an ingrown hair, which can increase inflammation, prolong healing, or cause a skin infection.

Can an Ingrown Hair Cause a Hard Lump in the Armpit?

Ingrown hairs usually only lead to small bumps. Call your doctor if you notice signs of an infected ingrown hair, such as a large cyst or increased pain or swelling. They can help remove the hair and treat any infection to prevent more problems.

How Are Infected or Recurrent Ingrown Hairs Treated?

If needed, your health care provider can cut into the affected area and release the ingrown hair using a sterile knife and tweezers. They may also prescribe antibiotic pills (often tetracycline or flucloxacillin) or topical ointments (often erythromycin or clindamycin), retinoids (isotretinoin) to encourage turnover of dead skin cells, or steroid creams to lessen inflammation.

If the problem is severe or keeps coming back, your doctor can perform a procedure called electrolysis, which damages individual hair roots with an electrical current. You can also consider laser hair removal to destroy the growth of dark underarm hair.

Recognizing Related Conditions

If ingrown hairs are a recurring or debilitating problem, you may have another underlying skin disease. Folliculitis is a similar problem when the hair follicle becomes infected (but not necessarily from an ingrown hair). It may be confused for an acne breakout. Some people develop folliculitis after using a hot tub, wearing a wet bathing suit for too long, or exercising in tight clothing.

Hidradenitis suppurativa (HS) is a painful condition that can produce lumps in the armpits, groin, and other areas of the body. HS often looks like ingrown hairs or acne, but it’s an ongoing condition with periods of flaring (worsening symptoms) and remission. On myHSteam, members discuss how they finally realized that their skin sores were caused by something more than ingrown hairs.

“I battled with HS for several years before that without realizing what it was. I just thought I was getting a lot of ingrown hairs,” shared a member of myHSteam. “I even resorted to laser hair removal. But when the bumps kept coming back, I saw my doctor, who referred me to a dermatologist, where I was ultimately diagnosed.”

Another member explained, “I’m pretty sure shaving and ingrown hairs caused my HS to begin with. I had an ingrown hair cyst that took months before being cut. When abscesses can’t drain, they tract and tunnel, and then that tract or tunnel can continue to fill up. … I only use trimmers now, and I don’t cut the hair too short because short hair pokes into the skin around it and has caused flare-ups from friction.”

As a rare skin condition, doctors don’t always recognize HS right away. They may assume you have another issue like ingrown hairs, when the problem is deeper. If you think you’ve been misdiagnosed, ask for a second opinion. You shouldn’t have to accept painful ingrown hair cysts as a normal part of life. Instead, seek answers and solutions to heal your discomfort.

HS significantly affects quality of life, especially when it’s not treated properly. It can be helpful to learn from others who have experienced similar challenges. Joining support groups or online forums can help you learn useful tips and ways to cope. Sharing your experiences and hearing from others can also make you feel less alone and more in control of your condition.

Talk With Others Who Understand

On myHSteam, the social network for people and their loved ones living with hidradenitis suppurativa, more than 40,000 members come together to ask questions, give advice, and share their stories with others who understand.

Have ingrown hairs caused you to stop shaving your underarms? Do you use alternative hair removal techniques or over-the-counter home treatments to prevent ingrown hairs? Share your experience in the comments below, or start a conversation by posting on your Activities page.