Painful skin lump: causes and warning signs

A boil or abscess often feels tender and may develop a central area of pus. Cellulitis more often produces spreading warmth, redness, and swelling around the affected skin. Repeated painful lumps in the armpits, groin, or under the breasts may point toward hidradenitis suppurativa. Shingles can begin with pain or sensitivity before a one-sided cluster of blisters appears. A clinician also considers injury, an inflamed cyst, an insect reaction, or a deeper lump based on its location and behaviour.

Do not squeeze, cut, or repeatedly press the lump. Keep it clean, wear loose clothing, and avoid shaving or rubbing over the area. If it opens, cover it with a clean dressing and wash your hands after changing it. Note when it started, whether it is growing, and whether the skin around it is hot or spreading. Arrange a medical assessment for a persistent, recurrent, enlarging, or very tender lump because treatment depends on the cause.

Seek prompt care if the lump is rapidly enlarging, hot, draining pus, surrounded by spreading redness, or accompanied by fever or marked illness. Seek urgent assessment for red streaks, severe pain out of proportion to the appearance, a lump near the eye, or trouble moving the nearby area. Emergency help is needed for breathing difficulty, facial or throat swelling, confusion, or faintness.

Ask what the lump most resembles, whether it needs drainage or another procedure, whether the skin should be swabbed, how to dress it, and what changes mean you should return sooner.