Cold sores are small blisters that occur most often on the lips or mouth. Usually caused by type I of the herpes simplex virus, cold sores can be transmitted from one person to another. Even if a cold sore is not present, the virus can spread through infected saliva. Once the fluid-filled blisters have dried, the risk of spreading the virus to another person is reduced. Certain things can activate recurrences of cold sores. These include fever, stress, a weakened immune system, hormonal changes often associated with menstruation, or prolonged exposure to the sun.
When in the dormant stage, the virus lies inactive near the back of the jaw on the side where the cold sore normally develops. When you are under stress or your immune response is lowered, the virus can be triggered and begin to reproduce. You may feel an itch or tingle at the area where the blister eventually will erupt. Once the virus reaches the surface of the skin, swelling and redness appear at the site. At this stage, you will notice tiny red bumps, similar to pimples, that are painful and sensitive to the touch.
Besides being unsightly, an open cold sore is painful and at its most contagious stage. You should not touch a cold sore blister, as you could spread the virus to another part of your body or to someone else. When the cold sore develops a yellowish crust or scab, it will begin healing from the inside out. You may experience more itching and pain, as new skin forms under the scab. Even when the cold sore no longer is visible, healing continues beneath the skin. It can take up to 10 days for a cold sore to heal completely. The virus then lies dormant again in the skin until something triggers another breakout at or near the same site.
While cold sores will usually heal on their own without any special treatment, applying ice to the blister can reduce redness and swelling. You also can boost your immune system by getting enough rest and taking vitamins and mineral supplements. Eat a balanced diet of green vegetables, fruits and protein. To reduce pain and discomfort, take an over-the-counter pain reliever. If you tend to get cold sores often, always wear sunscreen on your face and lips whenever outdoors. Keep plenty of lip balms with sunscreen on hand. Since the virus is highly contagious, do not drink from someone else’s glass or share eating utensils. Avoid skin contact with anyone who has visible cold sores.