An ingrown nail happens when the edge of your nail grows into the surrounding skin instead of over it. Sharp fragments along the side of the nail gradually push into the soft tissue of the nail groove, and your body treats the nail like a foreign object, triggering pain, swelling, and sometimes infection. The big toe is the most common site, though any toenail (and occasionally a fingernail) can be affected.
How an Ingrown Nail Develops
Your nail normally sits in a groove along each side of the nail bed. When something disrupts that fit, small spicules along the lateral edge of the nail start digging into the skin. As the nail continues to grow, it drives deeper. The body launches an inflammatory response at the penetration point: the skin reddens, swells, and can begin producing pus. If left untreated, a mass of extra healing tissue called granulation tissue can form over the nail edge, making the problem progressively worse.
Common Causes
Several factors contribute, and most ingrown nails result from more than one at the same time.
- Trimming too short. Cutting the nail so short that it no longer reaches past the skin folds on the sides gives it room to slip sideways and penetrate the nail bed.
- Tight footwear. Shoes that compress the toes push the skin ridges against the relatively stiff nail, effectively turning the nail into a cutting edge pressed into soft tissue.
- Trauma. Stubbing your toe, dropping something on it, or repetitive pressure from running can damage the nail or push it off track.
- Genetics. Some people inherit naturally curved or pincer-shaped nails that are more prone to growing into the surrounding skin.
- Infection. A fungal nail infection can thicken or warp the nail plate, changing its shape enough to cause ingrowth.
The Three Stages
Ingrown nails are classified into three stages based on severity, and knowing which stage you’re in helps determine whether you can manage it at home or need professional care.
Stage 1: Mild
The end of the toe is red and slightly swollen. It feels warm and hurts when you press on it, but there’s no pus or drainage. This is the easiest stage to treat on your own.
Stage 2: Moderate
Redness and swelling increase noticeably. White or yellow pus may begin draining from the area, a sign that infection has likely set in. The pain is more constant and doesn’t require pressure to trigger it.
Stage 3: Severe
Granulation tissue, a red, beefy-looking mass of new tissue, forms alongside the nail and adds to the swelling. The skin fold next to the nail may grow over part of the nail itself. Pus discharge is heavier. In some cases, the infection can spread enough to cause fever.
Managing a Mild Ingrown Nail at Home
Stage 1 ingrown nails often resolve with consistent home care over one to two weeks. The goal is to reduce swelling, keep the area clean, and give the nail room to grow out past the skin edge.
Soak your foot in warm water mixed with 1 to 2 tablespoons of unscented Epsom salt per quart of water. Keep your foot in the soak for about 15 minutes at a time, and repeat several times a day for the first few days. After soaking, gently dry the toe and apply a thin layer of antibiotic ointment if the skin is broken. Wear open-toed shoes or sandals when you can to reduce pressure on the nail.
Some people try to wedge a small piece of cotton or dental floss under the nail edge to lift it away from the skin. This can work for very mild cases, but it also introduces a risk of pushing bacteria deeper into the wound. If you try it, change the material daily and stop if pain increases.
If you see pus, increasing redness, or no improvement after a few days, the nail has likely progressed beyond what home care can fix.
Professional Treatment Options
For stage 2 and stage 3 ingrown nails, or for stage 1 cases that don’t respond to soaking, a podiatrist or other clinician can perform an in-office procedure. The most common approach is partial nail avulsion, where the offending strip of nail along the side is removed under local anesthesia. The procedure itself takes only a few minutes.
The catch with a simple avulsion is recurrence. When the nail root is left intact, the same strip of nail grows back, and the ingrown nail returns roughly 70% of the time. To prevent this, clinicians typically combine the avulsion with a chemical treatment that destroys the portion of the nail root responsible for that strip. A Cochrane review found that this combination dropped recurrence dramatically: about 1 in 25 patients experienced a return of symptoms, compared to 8 in 21 patients who had the nail removed without the root treatment.
What Recovery Looks Like
After a procedure, you’ll keep the toe bandaged day and night for the first week, then transition to leaving it uncovered at night during the second week. Plan to reduce your activity and rest your foot for about two weeks. Most people return to normal daily routines within one to two weeks, though getting back to sports or high-impact exercise takes a bit longer. The toe may be tender and drain small amounts of fluid for several weeks as the nail bed heals underneath.
Preventing Ingrown Nails
The single most effective habit is cutting your toenails straight across rather than rounding the corners. When you curve the edges, you create a sharp point that’s primed to dig into the skin as the nail grows forward. The American Academy of Dermatology recommends this straight-across technique specifically to reduce ingrown nail risk. Leave the nail long enough that the edge sits roughly even with the tip of the toe rather than cutting it short.
Footwear matters just as much. Shoes should have enough room in the toe box that your toes aren’t being squeezed together. This is especially important for runners and anyone on their feet all day. If you’re prone to ingrown nails, avoid pointed-toe shoes entirely.
People with naturally curved nails or recurrent ingrown nails may benefit from periodic professional nail care. Diabetics and anyone with poor circulation in the feet should be particularly careful, since even a mild ingrown nail can progress quickly when healing is impaired.