Cortisone shots, antiviral prescription and over-the-counter remedies, eye drops and cold compresses are all treatments that improve the appearance of cold sores quickly, notes Huffington Post. Using concealer or face powder doesn't work because when the surface breaks, the fluid forms a crust with the cosmetics.
An injection of diluted cortisone into a cold sore reduces swelling very quickly, reports Huffington Post. A prescription for an antiviral such as Valtrex or Acyclovir also brings the cold sore down, although not as quickly. Abreva, available over-the-counter, decreases the discomfort and size of cold sores. Eye drops such as Visine take the redness out of cold sores, as does application of a cold compress to the sore for 20 minutes.