How to treat cold sores. There are many that you can do at home to soothe the sting of a cold sore, such as: Ice. You can numb the pain if you apply a cold compress to the sore. Don’t put ice directly on your skin-- that could damage it. Pain relievers. When a cold sore really stings, you may get some relief from an over-the-counter painkiller like acetaminophen. Over-the-counter creams. There are products available at the drugstore that can help reduce the pain of a cold sore or help keep the skin soft while it heals. Aloe vera gel. The same gel used for sunburn may help a