What should you know about acute cellulitis?

It typically causes an expanding area of red, warm, swollen, or painful skin. Treatment should start promptly because the infection can spread through surrounding tissue or, less often, beyond the skin.

Bacteria can enter through a cut, crack, ulcer, insect bite, or another break that is too small to notice. The lower leg is often involved, but cellulitis can develop on other body regions. The affected patch generally has poorly defined edges rather than a sharply outlined ring.

Cellulitis often presents with skin redness, swelling, warmth, and tenderness; fever or chills may occur when the illness is more systemic. Athlete's foot can create cracks between the toes that provide an entry point. Diabetes, poor circulation, or persistent swelling can increase vulnerability and may affect treatment planning.

Arrange a same-day clinical assessment if you suspect cellulitis. A clinician usually diagnoses it by examining the skin and checking for a possible entry wound; tests may be needed if the diagnosis is unclear or the infection seems severe.

Take prescribed antibiotics exactly as directed and complete the course. Resting and elevating an affected arm or leg can ease swelling. Keep broken skin clean, avoid squeezing the area, and note whether redness continues to expand after treatment begins.

Seek urgent medical care for rapidly spreading redness, severe or escalating pain, blistering, dark or numb skin, marked drowsiness, confusion, fast breathing, faintness, or feeling severely unwell. Redness near an eye also warrants urgent assessment.

Emergency help is appropriate if signs suggest sepsis, such as confusion, breathing difficulty, mottled or unusually pale skin, or collapse. Contact the treating clinician promptly if symptoms worsen despite antibiotics or fail to begin settling as expected.

Ask which skin break may have allowed infection, whether the border should be monitored, and when improvement should become noticeable. Also discuss wound care, pain relief, medicine allergies, and whether athlete's foot, diabetes, leg swelling, or circulation problems need additional management to reduce recurrence.