Toenails are generally pretty innocuous. They’re rarely threatening (except, of course, when toenail clippings fly across the room like tiny bits of organic shrapnel at slightly less than the speed of sound). Usually, toenails grow straight out, keeping a nice noninterference policy with the rest of the toe. There are times, however, when nails begin to turn on you. One or both of the sides or corners of the nail begin to curve downward into the toe, causing the skin around the nail to become irritated and painful. At times, the nail may even penetrate the skin, letting in bacteria that decide that the toe is a fabulous place to live (and these are guests you definitely don’t want to have around).

There are many possible causes or contributing factors for ingrown toenails. If you have a family history of malevolent nails, or if you have nails that already seem to curve down on the sides, you may be susceptible. Pressure on your toes from too-tight shoes or socks may also lead to ingrown toenails, as can trauma (like stubbing your toe on the corner of your bed in the middle of the night, dropping a brick on your foot, or kicking a soccer ball (or bowling ball, for that matter) a bit too hard). Certain nail conditions, such as fungal infections in your nail bed may also contribute.

Improper trimming of your toenails may also be a significant factor. Cutting nails too short (you should be able to get your fingernail under the sides and end of your newly trimmed toenail) or trimming down the sides of the nail (you should trim straight across) can lead to problems. Peeling or tearing the corners of the nail can also be harmful.

Oh. And keep in mind that, while ingrown toenails most commonly occur on the big toe, any toenail may be affected.

Your first clue that your nail has gone from friendly to malicious is inflammation around your toenail. This will manifest itself as pain, warmth, redness, and swelling. You may also develop a callus along the side of your nail in response to an increase in pressure from your ingrown toenail and the associated swelling. Or, it’s possible that you’ll just have a toenail that appears to go pretty deeply down into your skin. If an infection develops, things usually get a little more nasty. You may notice drainage accompanied by a bad smell, and there may be a collection of pus. (Yes. It’s pretty gross.)

If you suspect you have an ingrown toenail, it’s probably best to go see your podiatrist about it, especially if infection is present. Definitely see your foot doctor if you have diabetes, nerve damage, or poor circulation in your foot. Your podiatrist should be able to make the diagnosis by performing a physical exam of your toe. (X-rays and such are pretty much unnecessary in diagnosing an ingrown toenail.)

If you do not have an infection in your toe, you may be able to get away with just doing some home treatments (unless you’re diabetic or have nerve or circulation problems in your foot). You can soak your foot in warm water or salt water three or four times a day, and gently massage the sides of your nail to help reduce inflammation. Then, apply antiseptic and a bandage over your toe. You may want to wear shoes, like sandals, that put no pressure on your toe while it heals. Don’t try to perform the endearingly named “bathroom surgery” by attempting to cut out the ingrown portion of your nail yourself. Also, (although you may have heard different from your best friend’s mother-in-law’s cousin’s wife) doing things like cutting a V- shape in the end of your toenail is pretty much useless. (Some believe that it allows the edges of an ingrown nail to grow together, but nail growth depends on the nail root, not the end of the nail. The V-method simply doesn’t work.)

If your nail fails to improve, or if you have an infection in your toe or other medical problems, your podiatrist can help bring your ingrown toenail back from the dark side. He or she will likely inject a local anesthetic into the area and remove the side of the nail that’s causing the problem. Your podiatrist may also opt to destroy the portion of your nail root that’s contributing to the ingrown nail (especially if this is a recurring problem for you). This may be done by using acid to destroy the root, or by using a laser. (Who knew treatments for ingrown toenails could be so close to science fiction?) Your podiatrist will also likely prescribe an antibiotic to clear up the infection in your toe. (Be sure to take all of the prescribed medication, by the way, even if your symptoms appear to have cleared up.)

You’ll probably want to stay off your foot and keep it elevated for a few hours, but you should be able to resume many normal activities the next day (although you’ll want to avoid vigorous movements like running for about two weeks). Occasionally, the entire nail may fall off after surgery; a new nail will grow over the next few months, although it will probably be a bit more narrow if your podiatrist has destroyed a portion of the nail root.

With the ingrown portion and accompanying infection taken care of, your toenail should reassume that harmless nature we love so well. Just treat it as well as you can, or it may show its destructive side once again.