Hand swollen after a spider bite: what to know

Many suspected spider bites are difficult to identify, and a painful red bump may instead be an irritated follicle, another insect bite, or a small wound. Local inflammation can cause swelling, itching, tenderness, and warmth around the spot. Infection is more concerning when the area enlarges, becomes increasingly painful, produces pus, or is accompanied by fever. A darkening blister, spreading skin change, or worsening pain deserves clinical attention rather than home treatment alone. Hand swelling is a symptom, not proof of the creature involved.

Wash the area gently with soap and water, then cover broken skin with a clean dressing. Remove rings before swelling progresses, rest the hand, and keep it raised. A cool cloth may reduce discomfort; wrap cold items and use them briefly to protect the skin. Do not cut, burn, suck, or squeeze the bite, and do not apply unknown chemicals. Take a photograph and note the time, changes in colour, and any symptoms elsewhere.

Seek urgent help for trouble breathing, faintness, facial or mouth swelling, rapidly worsening pain, or fast spread of swelling. Obtain same-day assessment for fever, pus, red streaks, a spreading hot area, a dark or blistering centre, numbness, or difficulty moving the fingers. A hand that becomes pale, blue, cold, or tightly swollen needs immediate attention.

Ask whether the skin needs treatment for infection, whether the joint or tendon is involved, and which medicines are appropriate with your conditions. Share a photo if the appearance changed and describe the speed of swelling.