What should you know about an inflamed cyst on your back?

A cyst is a closed sac beneath or within the skin. When its wall becomes irritated or its contents leak, the area can feel sore, firm, swollen, or hot. Bacterial infection may also produce pus, increasing redness and tenderness. A painful lump is a symptom, not a diagnosis, so a clinician may need to examine it, especially if the lump is new, changing, or difficult to identify.

Do not squeeze, puncture, or repeatedly press the lump. Those actions can push inflammation deeper, break the skin, and make healing harder. Keep clothing and backpack straps from rubbing against it.

Wash the surrounding skin gently, pat it dry, and use a clean warm compress for short periods if that feels soothing. Cover any drainage with a fresh, non-stick dressing and wash your hands before and after touching the area. Avoid shaving over it and do not apply harsh antiseptics or leftover antibiotics without advice.

A clinician can decide whether observation, prescription treatment, drainage, or later cyst removal is appropriate. Drainage may relieve pressure, while removing the cyst wall can reduce recurrence but is usually considered after active inflammation settles.

Arrange prompt medical care if redness is spreading, pain is worsening, the lump is rapidly enlarging, or pus continues to drain. Seek urgent help for fever, chills, red streaks, marked weakness, or swelling that makes movement difficult. A back lump that persists, returns, bleeds, or changes should be assessed even if it is not painful.

Ask whether this is a cyst, whether infection is present, whether drainage is needed, and what care will protect the wound. If it returns, ask when removal of the cyst wall should be considered and how to reduce rubbing during recovery.