What should I do if a child's mosquito bite becomes very swollen and hard?

When a child is bitten by a mosquito and develops significant swelling and hardness, parents may take the following measures: 1. Clean the bite area: Gently wash the affected area with mild soap and warm water to prevent infection. 2. Apply a cold compress: Place a cold towel or ice pack gently on the bite for about 10 minutes at a time; this can be done multiple times daily to help relieve itching, swelling, and pain. 3. Apply topical medication: Use creams or ointments containing antihistamine ingredients, such as hydrocortisone cream, to reduce itching and swelling. Calamine lotion is also a good option, as it can relieve itching and provide a drying effect. 4. Prevent scratching: To avoid secondary infection caused by scratching, consider putting gloves on the child or trimming their fingernails. 5. Administer antiallergic treatment: If the child has a sensitive constitution and experiences severe swelling, oral antiallergic medications such as loratadine syrup or cetirizine drops may be considered, but only under the guidance of a physician. 6. Prevent infection: If signs of infection such as redness, swelling, pain, or pus appear at the bite site, seek medical attention promptly for appropriate anti-infective treatment. 7. Enhance mosquito prevention: To prevent further bites, apply insect repellent containing effective ingredients such as DEET before the child goes outdoors, and ensure they wear protective clothing such as long-sleeved shirts and long pants.