An ingrown fingernail happens when the edge of your nail grows into or presses against the surrounding skin, triggering pain, swelling, and sometimes infection. While ingrown nails are far more common on toes, they can and do occur on fingers, particularly the thumb. The good news: most cases resolve with simple home care if you catch them early.
How an Ingrown Fingernail Develops
Your nail sits inside a groove in the skin called the nail fold. Normally, about 1 mm of space separates the nail edge from the soft tissue of the groove, and a thin layer of skin protects that gap from irritation. When something disrupts this fit, a sharp sliver of nail (called a spicule) can dig into the skin along the side of the nail. Your body treats this like a foreign object and mounts an inflammatory response: the area gets red, swollen, and painful.
If the spicule keeps pressing deeper, it breaks through the protective skin layer entirely. That’s when infection becomes likely, because bacteria now have a direct path into exposed tissue.
Common Causes
The most common cause is cutting your nails too short. When you trim a nail aggressively, the skin at the sides can fold over the nail edge as it regrows, guiding it into the tissue rather than over it. Other frequent triggers include:
- Nail biting or picking: Tearing the nail creates jagged edges that easily catch on the nail fold.
- Trauma: Jamming a finger, dropping something on it, or repeated minor impacts (common in sports) can push the nail sideways into the skin.
- Curved nail shape: Some people naturally have nails that curve more sharply at the edges, making ingrowth more likely even with proper trimming.
- Fungal infections: These can thicken and distort the nail plate, increasing pressure on the surrounding skin.
What It Looks and Feels Like
Ingrown fingernails progress through three recognizable stages, and knowing where you are helps you decide how to respond.
Stage 1: Mild
The skin along one side of the nail looks slightly red and feels tender when you press on it. There’s mild swelling but no pus or drainage. This is the stage where home treatment works best.
Stage 2: Moderate
Redness and swelling increase noticeably. The area may feel warm, and you’ll likely see yellowish or whitish discharge where the nail meets the skin. Pain is more constant rather than only with pressure. Infection has set in at this point.
Stage 3: Severe
The inflamed skin begins to grow over part of the nail edge, forming red, bumpy granulation tissue. The lateral nail fold looks visibly thickened and puffy. Drainage is persistent, and the pain can be significant enough to interfere with using the affected finger.
Ingrown Nail vs. Paronychia
These two conditions look similar and can even overlap, but they’re not the same thing. Paronychia is an infection of the skin fold around the nail, often caused by bacteria entering through a hangnail, cuticle damage, or frequent hand washing. It typically causes a pocket of pus along the base or side of the nail without a nail edge actually embedded in the skin. An ingrown nail specifically involves the nail plate pressing into or piercing the tissue. That said, an ingrown nail can cause paronychia if the broken skin gets infected, so the two sometimes appear together.
Paronychia is actually more common on fingers, while ingrown nails are more common on toes. If your finger is red and swollen but you can’t see or feel a nail edge digging in, paronychia is the more likely culprit.
Home Treatment for Early Stages
If you’re in stage 1 or early stage 2, warm soaks are your first move. Mix 1 to 2 tablespoons of Epsom salt into a quart of warm water and soak the affected finger for 15 minutes at a time. Do this several times a day for the first few days. The warm water softens the nail and the surrounding skin, reduces swelling, and helps draw out any early infection.
After soaking, try to gently lift the nail edge away from the skin using a clean cotton wisp or a small piece of dental floss tucked under the corner of the nail. This redirects growth away from the tissue. Apply an over-the-counter antibiotic ointment and cover with a bandage. Repeat the process daily until the nail grows past the point where it was digging in.
Resist the urge to cut a V-shape in the center of the nail or dig aggressively at the embedded edge. Both are common folk remedies, and both tend to make things worse. Cutting a V does nothing to change how the nail grows from the root, and aggressive digging can introduce more bacteria into already irritated tissue.
When Professional Treatment Is Needed
If home care hasn’t improved things within a few days, or if you’re clearly in stage 2 or 3, a doctor can address the problem more definitively. The most common in-office procedure is a partial nail avulsion: the provider numbs your finger, then removes the strip of nail that’s embedded in the skin. This provides immediate relief and lets the area heal.
For nails that keep coming back ingrown in the same spot, a chemical matrixectomy is the next step. After removing the offending nail strip, the provider applies a chemical to the exposed nail matrix (the tissue that generates new nail growth) to permanently prevent that sliver from regrowing. Studies show this approach has a success rate above 95%, with recurrence rates between 1% and 4% over follow-up periods of six months to nearly three years. By comparison, simply removing the nail strip without treating the matrix leads to recurrence in roughly one out of three cases.
If a full nail removal is ever necessary, fingernails regrow in about 4 to 5 months for most adults. One documented case of a thumbnail regrowing after surgical removal took 33 weeks to reach its full 18 mm length. Toenails take roughly twice as long.
Potential Complications
Most ingrown fingernails are annoying rather than dangerous, but ignoring an infected one can lead to problems that escalate quickly. Cellulitis, a spreading infection of the skin and soft tissue, can develop if bacteria move beyond the immediate area. In rare cases, pockets of pus (abscesses) form and need to be drained. Even rarer but possible is osteomyelitis, an infection of the underlying bone that requires prolonged treatment.
People with diabetes, poor circulation, or weakened immune systems face higher risks from any nail infection. The reduced blood flow and impaired healing in these conditions mean what starts as a minor ingrown nail can progress to a serious infection more rapidly than it would in someone with normal circulation.
How to Prevent Ingrown Fingernails
The American Academy of Dermatology recommends cutting fingernails almost straight across, then using a nail file or emery board to slightly round the corners. This approach keeps the nail strong, prevents it from catching on things, and reduces the risk of sharp edges growing into the skin. Use proper nail clippers or nail scissors rather than tearing nails by hand.
A few other habits help. Keep nails at a moderate length rather than cutting them very short. If you bite your nails, that’s one of the most reliable ways to create the jagged, uneven edges that lead to ingrowth. Wearing gloves during activities that could jam or crush your fingers protects against trauma-related ingrowth. And if you notice your nails becoming thickened, discolored, or brittle (signs of a fungal infection), treating the infection early prevents the nail distortion that makes ingrowth more likely down the line.