Ingrown hairs are hairs that have curled round and grown back into the skin.
They produce raised red spots, which can sometimes become infected and turn into painful pus-filled sores.
Ingrown hairs can be itchy and embarrassing, but they often go away on their own without having to do anything.
Anyone can get them, but they tend to be more of a problem in people with curly or coarse hair.
Ingrown hairs have usually grown out of the skin, curled back round and re-entered the skin. Some curl back into the follicle without even exiting the skin.
It can happen when the hair follicle becomes clogged with dead skin cells. This forces the hair inside it to grow sideways, which is much more likely to happen if the hair is already curly or coarse, and if you've recently shaved the hair.
Ingrown hairs are particularly a problem where you shave – the beard area in men, and the legs, armpits and pubic area in women – because the hair that grows back has a sharper edge and can easily poke back into the skin.
They show up like pimples in the skin, and sometimes you can see the hair trapped beneath the skin. The spots can be filled with pus.
Don't pick or scratch at the ingrown hair, as bacteria can enter the small wound this creates, increasing your risk of infection. You might also be left with a scar.
Squeezing the spots can also damage the skin and cause infection.
If you must, use a sterile needle or set of tweezers to gently tease the hair out of the skin if it's near the surface. Don't dig for it if the hair lies deep.
But if you can, leave the ingrown hairs for a while as they may go away without having to do anything.
Men who are prone to ingrown hairs around their face may find it best to grow out their beard – longer hairs aren't as sharp at the ends, so are less likely to become ingrown.
The hair follicles of ingrown hairs can sometimes become infected and inflamed, which is known as folliculitis.
The hair follicles will swell into pus-filled spots (although note that pus doesn't always indicate infection).
Again, mild cases of folliculitis often clear up without treatment, so try stopping shaving for a few days and see if it gets better.
You could also try dabbing mild antiseptic such as tea tree oil.
If the spots don't improve and are bothering you, see your doctor. If one particular spot is a problem, your doctor may be able to release the hair using a sterile needle.
You would generally only need antibiotics if the skin is severely infected, with pustules and abscesses.
The simplest way to prevent ingrowing hairs is to let your hair grow freely without shaving it. You may want to try this for a brief period, for relief from particularly bad spots.
If you don't want to stop shaving, try the following shaving tips:
Other hair-removal methods may be less likely to result in ingrowing hairs. For example, instead of shaving legs, you may want to try depilatory creams, electrolysis or laser removal.
There are many skin conditions that can easily be mistaken for ingrown hairs, including:
If you're unsure, see your doctor.
Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.