It usually takes at least 2-3 days for the swelling to go down after a hornet sting, depending on the toxicity of the hornet. Hornet stings release venom that can irritate the skin and cause painful swelling. Allergy sufferers or those with more toxic wasps may experience serious adverse reactions such as hives, abdominal pain, diarrhea, difficulty breathing or swollen skin. Stings from less toxic wasps can also cause redness and swelling, usually without obvious clinical manifestations such as dizziness and nausea, and can be treated on their own. If you have been stung by a hornet, you should observe whether there is a residual stinger in the wound, avoid squeezing the stung area, use soap and water to wash it repeatedly after removing the stinger, and apply antihistamines locally to relieve the local redness and swelling, usually 2-3 days after the swelling and pain can be gradually reduced until it disappears. If pain occurs, pain relief medication can be taken to prevent the spread of inflammation. If the redness and swelling spreads and the pain is severe, it is necessary to go to a regular hospital for general surgery in time to prevent anaphylaxis. In addition, avoid spicy and irritating foods in daily life to avoid stimulating the wound and aggravating the swelling and pain.