Want to give unsightly cold sores the kiss off? Contending with cold stores is never easy. Cold sores, aka fever blisters, are caused by herpes simplex virus type 1 infection. Cold sores usually last between 10 and 14 days and are usually preceded by pain or tingling in the area. Once that occurs, a fluid-filled blister forms around the mouth. In addition to being an embarrassing eyesore, cold sores can be downright painful. Many physicians prescribe lidocaine for pain relief and zilactin to lessen the flare ups. There are also a host of oral medications including Valtrex, Famvir and other drugs that reduce the sentence while relieving the pain if taken early on. Other treatment plans include alternating between ice packs and warm compresses and using ointments such as lidocaine and benzocaine for discomfort. One of the major no-nos is messing with the sore. As tempting as it may be, don't ever squeeze, pinch or pick at a blister.