What should you know about sudden swelling in one hand?

Swelling may develop after a knock, fall, sprain, tight jewellery, repetitive use, or an insect bite. A fracture near the wrist can cause swelling, tenderness, bruising, and difficulty using the hand; see [Distal Radius Fracture](/conditions/distal-radius-fracture/) for related information. Inflammation can affect several small joints, sometimes with warmth and morning stiffness, as may occur with [Rheumatoid Arthritis](/conditions/rheumatoid-arthritis/). Skin that is hot, increasingly red, or very tender raises concern for infection. Swelling with unusual colour, coldness, or numbness needs prompt assessment because blood flow or nerve function may be affected.

Remove rings, bracelets, and anything tight before swelling increases. Rest the hand, keep it raised when possible, and use a wrapped cold pack for short periods if an injury seems likely. Do not force stiff fingers or massage an area that is hot, very painful, or rapidly changing. Compare colour, temperature, sensation, and movement with the other hand. Arrange a clinical assessment if swelling persists, returns, or limits normal use; note when it began and any recent injury, new activity, bite, wound, or medication change.

Seek urgent medical care if the hand becomes blue, pale, cold, or numb; swelling is rapidly worsening; pain is severe; fingers cannot move; there is an open wound, obvious deformity, fever, or spreading redness; or swelling follows a significant injury. Sudden weakness of the whole arm, facial drooping, trouble speaking, chest discomfort, or breathlessness requires emergency help.

Ask what examination or imaging may clarify the cause, whether a joint or tendon is involved, how to protect movement safely, and which changes should prompt a faster review.