What Causes Skin Swelling?

A sudden puffy area with itching or raised welts can occur with hives or angioedema. Angioedema often affects deeper skin around the lips, eyelids, hands, or feet. Swelling that is warm, tender, red, and spreading can occur with cellulitis, a skin infection. A bruise, insect bite, contact with a product, or a knock can also produce a local response. Swelling in both legs or around a joint may have a different cause and deserves context about medicines, circulation, and other symptoms.

Note when the swelling began, where it started, whether it is spreading, and whether itching, pain, warmth, rash, fever, or drainage is present. Stop using a newly introduced cosmetic or topical product on the area. Keep the skin clean and avoid scratching. A cool compress may ease itch or discomfort when the skin is intact; avoid squeezing a lump or applying unfamiliar creams. A clinician can examine the pattern and decide whether allergy treatment, infection treatment, or another approach is appropriate.

Get emergency help for swelling of the lips, tongue, mouth, or throat, trouble breathing, faintness, or rapidly worsening symptoms. Arrange prompt medical assessment for swelling with fever, severe pain, spreading redness, pus, red streaks, or marked warmth. Seek advice if swelling keeps returning, follows a new medicine, affects an eye, or does not settle as expected.

Could this pattern fit an allergic reaction, infection, or another cause? Which medicines, foods, or skin products should I review? What changes would mean I need urgent help?