What should you know about tender lump in forearm under skin?

Tenderness often reflects inflammation, pressure, irritation, or infection, but it does not identify the cause by itself. A boil can become red, warm, and increasingly painful as infection develops. A cyst or other benign lump may feel smooth or mobile, while a deeper nodule may be harder to define from the surface.

A clinician will consider when it appeared, whether it is growing, whether the skin is changing, recent injury or insect bite, medicines, and symptoms such as fever or reduced movement. Skin cancer can sometimes present as a changing or persistent growth, so an unusual lesion should not be diagnosed from touch alone.

Measure change by noting the location and appearance rather than repeatedly pressing it. Keep the skin clean, avoid squeezing or piercing the lump, and protect it from friction. If it resembles a small boil, a warm clean compress may be soothing, but stop if pain or redness increases. Do not apply leftover antibiotics or steroid cream without professional advice.

Book a medical examination if the lump remains, enlarges, recurs, or interferes with movement. Depending on the findings, care may involve observation, drainage, imaging, or a treatment such as an intralesional steroid injection for a suitable inflammatory lesion.

Seek prompt care for rapidly expanding redness, severe pain, warmth with pus, fever, red streaks, numbness, weakness, or difficulty moving the hand or arm. Urgent assessment is also appropriate after significant injury or when the lump feels fixed and is changing. Do not wait for it to rupture or attempt to drain it yourself.

What features suggest a boil, cyst, inflamed nodule, or another growth? Does the lump need imaging or sampling? Which changes should prompt urgent review, and would an intralesional steroid injection be appropriate for the suspected cause?