In most cases, patients are advised to spray Yunnan Baiyao aerosol 1 day after the sprain. Foot sprains are very common in clinical practice, and patients should judge for themselves whether the sprain is accompanied by a fracture. If the sprain is simple, it is best to go to a public hospital to check for serious ligament damage. A mild sprain can be treated at home by elevating the affected limb and icing the limb for 2-3 days. The purpose of ice is to relieve pain on the one hand, and to reduce bleeding and swelling brought on by capillary damage on the other. Yunnan Baiyao aerosol is a drug with the effect of activating blood circulation and resolving blood stasis, which can well relieve local pain. The use of Yunnan Baiyao aerosol can increase local bleeding in the early stage, so it is recommended that for patients with acute sprains, it is best to use Yunnan Baiyao aerosol for swelling treatment after 1 day when the bleeding of local tissues is reduced and swelling is stable.