How to prevent: There’s no such thing as too much lip balm. It’s your first line of defense against chapped lips, says Jayne Fortson, a dermatologist in Anchorage, Alaska. Try ChapStick or Carmex, which contain a moisturizing ingredient such as lanolin or petrolatum. Wear a lip balm with SPF if you plan on spending more than 30 minutes outside. Try Dermatone Meicated Lip Balm SPF 23 ($3, dermatone.com). Unlike many balms, it won’t crystallize in cold weather. Says Leddon, “Also, avoid licking your lips. That dries them out even more.”
How to treat: Coat lips a couple of times a day with a heavy-duty emollient, such as Aquaphor Healing Ointment, which seals moisture into skin. “That should rehydrate lips within a day or two,” Felderman says.
When to see a professional: Painful cracks at the corners of the mouth are signs of perleche, a type of yeast infection, or a cold sore, which may require a prescription ointment.