What Are the Signs & Symptoms of a Cold Sore Coming on?

Caused by outbreaks of the Herpes Simplex Virus (HSV,) cold sores are annoying, unsightly blisters which commonly occur on or around the mouth. The virus is spread through close contact with other infected people, and the University of Maryland Medical Center estimates that 90 percent of American adults have been exposed to the virus. There is no known cure for HSV, but prescription medications greatly decrease the number of outbreaks, according to the American Academy of Dermatology.

Tingling

• The tingling feeling that precedes a cold sore usually occurs one or two days before the cold sore appears. The tingling commonly occurs around the mouth or nose, according to the University of Maryland Medical Center. This tingling can be an annoyance and in some cases feels more like a burning or itching sensation.

Redness

• As the cold sore begins to develop, the tingling area will become red and irritated. This redness becomes a raised blister, filled with fluid, that lasts between 10 and 14 days, according to the Mayo Clinic. Medical help is not necessary for a run-of-the-mill cold sore, but you should consult a physician if the sore does not heal within two weeks or if you develop an eye infection, according to the American Academy of Dermatology.

Sore Throat

• In some cases, a sore throat occurs before and during the cold-sore outbreak, according to the University of Maryland Medical Center. Swollen lymph nodes in the neck may accompany the sore throat. These should disappear in time along with the blister.