An infected nail bed typically shows redness, swelling, and tenderness in the skin immediately surrounding the nail. In more developed infections, you may see a visible pocket of pus forming under the skin next to the nail or beneath the nail itself. The area often feels warm to the touch and throbs with pain. What the infection looks like depends on whether it came on suddenly or has been building slowly, and whether bacteria or fungus is the cause.
Acute Infections: Sudden and Painful
An acute nail bed infection, called paronychia, appears rapidly, often within hours of a hangnail tear, nail biting, or a cut near the cuticle. The hallmarks are hard to miss: the skin along one side of the nail or at the base becomes swollen, red, and warm. The redness is usually concentrated rather than diffuse, forming a tight band of inflamed tissue right at the nail fold. Pain is throbbing and constant, not just tender when touched.
As the infection progresses, you may notice a small white or yellowish area forming near the nail edge. That’s pus collecting beneath the skin. Sometimes the pus sits visibly under the nail plate itself, giving part of the nail a cloudy, whitish-yellow appearance. In most cases, only one nail is affected. The swelling can make the skin look stretched and shiny, and pressing on it may reveal a soft, fluid-filled feeling beneath the surface.
Chronic Infections: Subtle but Persistent
Chronic nail bed infections develop slowly over weeks, and they look different from the dramatic redness of an acute case. The skin around the nail is mildly swollen, tender, and pink rather than bright red. One of the most distinctive signs is a missing or receded cuticle. The skin surrounding the nail often feels soft, moist, or “boggy” when you press on it, rather than firm and taut.
Unlike acute infections, chronic paronychia frequently affects several nails on the same hand at once. People who regularly have wet hands (dishwashers, bartenders, healthcare workers) are especially prone. The nails themselves may develop ridges, discoloration, or an uneven surface over time as the ongoing inflammation disrupts nail growth. These infections can persist for weeks to months, with occasional flare-ups of more intense pain and swelling layered on top of the baseline irritation.
Bacterial vs. Fungal: Color Tells the Story
The color of the nail and surrounding skin offers a useful clue about what’s causing the infection. Bacterial infections tend to produce rapid redness and white or yellow pus. If the nail itself develops a green or black discoloration, that points to specific bacteria like Pseudomonas, which produces pigments as it grows.
Fungal nail infections look quite different. They typically start as a white or yellow-brown spot under the tip of the nail. Over time, the nail thickens, becomes brittle, and crumbles at the edges. The discoloration spreads inward from the tip toward the base. Fungal infections are rarely painful in the early stages, which is one way to distinguish them from bacterial infections that hurt almost immediately. You may also notice debris building up under the nail, giving it a lifted, chalky appearance.
Chronic paronychia often involves a combination of fungal and bacterial organisms, which is why the nail fold stays irritated even after a round of antibiotics.
What a Worsening Infection Looks Like
Most nail bed infections stay localized, but some spread. If redness begins extending beyond the skin immediately around the nail, moving up the finger or across the hand, the infection may be reaching deeper tissues. Red streaks tracking away from the nail toward the wrist are a particularly important warning sign, as they suggest the infection is traveling along lymph channels.
Other signs that an infection is getting worse include:
- Increasing warmth that spreads beyond the nail area
- Fever or chills, which suggest the body is fighting a systemic infection
- Blistering or dimpling of the skin near the nail
- A rapidly expanding rash around the finger or toe
A swollen rash that’s changing quickly or accompanied by fever warrants emergency care. A growing rash without fever should still be evaluated within 24 hours.
Why Some People Are at Higher Risk
For most healthy people, a nail bed infection is uncomfortable but manageable. For people with diabetes, poor circulation, or a weakened immune system, these infections can escalate quickly and heal slowly. Diabetes in particular raises the risk of severe, chronic paronychia because reduced blood flow to the extremities limits the body’s ability to fight infection at the site.
If you have diabetes or any condition that affects circulation or immune function, even a mild-looking nail infection, pink skin and slight swelling, deserves prompt attention. What looks minor on the surface can be more serious underneath when the body’s defenses are compromised.
What to Expect During Treatment
Early nail bed infections that show redness and swelling but no visible pus often respond to warm water soaks and oral antibiotics. You soak the affected finger or toe for 15 to 20 minutes several times a day, which helps draw the infection toward the surface and relieves pressure.
If a pocket of pus has formed, that fluid usually needs to be drained. A provider lifts the skin fold away from the nail or makes a small opening to release the trapped pus. This sounds worse than it feels, and relief is often immediate because draining the pocket removes the pressure causing most of the pain.
Acute infections that are caught early and treated typically improve within a few days. Chronic paronychia is a longer process. Even with consistent treatment, it often takes nine weeks or more for the nail fold to fully return to normal. Without treatment, chronic infections tend to follow a cycle of flare-ups: periods of relative calm interrupted by painful episodes as new organisms work their way into the damaged skin barrier.