An impacted toenail, more commonly called an ingrown toenail, is a condition where the edge of the nail grows into the surrounding skin instead of over it. The big toe is the most frequently affected. When the nail punctures the skin fold alongside it, the body treats that sharp edge like a foreign object, triggering inflammation, pain, and sometimes infection. The medical term is onychocryptosis, and it ranges from a mild annoyance to a serious problem requiring a minor procedure.
How It Happens
Your toenail normally grows forward in a straight line, sliding over the skin at the sides. An impacted toenail veers off course. The edge or corner of the nail digs into the soft tissue of the nail fold, and because the nail keeps growing, it pushes deeper. This sets off a chain reaction: the skin becomes inflamed, swells around the nail, and can eventually break down enough to let bacteria in. Once infection takes hold, the toe may ooze pus, bleed, and develop a foul smell.
Common Causes
Improper nail trimming is the single most common cause. Cutting nails too short, rounding the corners, or tapering them into a V-shape can leave a tiny spike of nail that acts like a blade against the skin. Tight shoes are the second major culprit, especially in the toe box where constant pressure pushes skin against the nail edge.
Other contributing factors include foot injuries, excessive sweating, poor foot hygiene, and certain medications (particularly some cancer drugs that affect skin and nail growth). Some people are simply built for it: naturally wide nail plates, pincer-shaped nails that curve inward, or a congenital misalignment of the toenail all increase the risk.
Symptoms by Stage
Doctors classify ingrown toenails into three stages based on severity:
- Stage 1: The nail edge presses into the skin. The side of the toe is red, swollen, and tender, especially when pressure is applied. There’s no drainage or open wound yet.
- Stage 2: New inflamed tissue, called a granuloma, forms at the edge of the nail. This tissue is raw-looking and granular, and the area starts weeping fluid or producing pus.
- Stage 3: The inflammation becomes chronic. Pus oozes regularly, the granuloma tissue begins growing over the nail itself, and the toe may smell noticeably bad.
Most people seek help at stage 1 or 2 because the pain makes wearing shoes difficult. By stage 3, the nail is partially buried under overgrown tissue and home care alone is unlikely to resolve it.
What You Can Do at Home
For a mild case (stage 1), soaking the affected foot in warm water for 15 to 20 minutes several times a day can soften the skin and reduce swelling. After soaking, you can try gently lifting the nail edge and placing a small piece of clean cotton or dental floss underneath to encourage the nail to grow above the skin. This technique works best when the nail is only slightly embedded.
What you should avoid is “bathroom surgery.” Digging into the side of the nail with scissors, clippers, or other tools can worsen the injury, push bacteria deeper into the wound, and create a jagged nail edge that makes the problem recur. If the toe is already red and oozing, home treatment is not enough.
Professional Treatment
A doctor or podiatrist has several options depending on severity. For a mildly ingrown nail, they may lift the nail edge and place a splint, a tiny slit tube that slides underneath the embedded portion. This holds the nail away from the skin while it grows out, typically over 2 to 12 weeks.
For more advanced cases with visible inflammation and pus, the standard approach is partial nail removal. The toe is numbed with a local anesthetic, and the ingrown portion of the nail is trimmed away. In many cases, a chemical called phenol is applied to the exposed nail bed to prevent that strip of nail from regrowing. This makes a significant difference in recurrence: one study of 140 patients found that partial removal with chemical treatment had a recurrence rate of about 1.4%, compared to 10% when the chemical step was skipped. The difference was even more dramatic in younger patients, where recurrence dropped from nearly 15% to zero with the added treatment.
Recovery After a Procedure
If you have part of your nail removed, healing typically takes six to eight weeks. Full nail removal takes eight to ten weeks. Most people return to work or school the next day, though the toe will be bandaged and tender. During recovery, you’ll want to avoid tight shoes, swimming, and intense physical activity until the site has fully closed. The toe may look a bit different permanently if a strip of nail was chemically prevented from regrowing, but the cosmetic change is minor and usually hidden by the remaining nail.
When Infection Spreads
An untreated ingrown toenail can progress to a condition called paronychia, a bacterial infection of the skin alongside the nail. The nail fold becomes intensely red, swollen, and warm, and an abscess (a pocket of pus) may form. If that abscess isn’t drained, the infection can tunnel under the nail to the other side, creating what’s known as a run-around abscess. In rare cases, the infection can spread to the tendons and deeper structures of the foot, which is a serious complication requiring urgent treatment.
People with diabetes face particular risk. Reduced blood flow and nerve damage in the feet mean an ingrown toenail may not hurt as much as it should, so the problem can advance without obvious warning signs. The CDC lists an ingrown toenail as a reason for someone with diabetes to see their doctor right away rather than managing it at home.
Preventing Recurrence
The most important prevention step is trimming your toenails correctly. Cut them straight across, leaving the corners long enough to rest loosely against the skin on either side. Don’t round the edges or cut them short. Use whichever tool you’re most comfortable with: nail clippers, scissors, or a file. If you have trouble reaching your feet or seeing them clearly, a professional pedicure or podiatry visit is worth it.
Shoes matter too. Your toes need room to move without the nail being pressed into the skin. If you notice redness forming along one side of a toenail after wearing a particular pair of shoes, that’s your signal to switch to something with a wider toe box. Keeping your feet clean and dry also helps, since moisture softens skin and makes it easier for a nail edge to penetrate.