A cold sore is a common viral infection caused by the Herpes Simplex Virus type 1 (HSV-1), which remains dormant in nerve cells. An outbreak manifests as a fluid-filled blister, typically on or around the lips, indicating the virus is actively replicating. The sore is highly contagious from the initial tingling sensation until it has fully healed. Avoiding specific actions and exposures during this active phase prevents transmission to others, stops the virus from spreading on your body, and ensures the fastest recovery.
Preventing Spread Through Contact
The sore is most contagious when the blister is actively weeping fluid, but transmission remains possible until it is completely healed. Direct physical contact with the lesion or infected fluid is the primary way the virus spreads. Avoid close physical intimacy, such as kissing, until the cold sore is entirely gone.
Refrain from engaging in oral sex during an outbreak, as the virus can spread to the genital area and cause a new infection. Be vigilant about not sharing personal items that touch the mouth, including eating utensils, drinking glasses, towels, razors, and lip products. The virus can survive on these surfaces, potentially spreading to others.
Self-transmission, known as autoinoculation, is a risk if you touch the sore and then touch another sensitive area. Wash your hands immediately with soap and water after applying topical treatment or accidentally touching the lesion. Never rub your eyes after touching the sore, as this can lead to a serious eye infection called ocular herpes.
Behaviors That Irritate the Sore
Physical manipulation of the cold sore delays healing and increases the risk of secondary bacterial infection. Strictly avoid picking, scratching, or squeezing the blister or the subsequent crusty scab. Disrupting the scab before the skin has fully repaired can cause bleeding, leave a scar, and re-open the wound.
Be mindful of activities that stretch the skin around the mouth, such as excessive yawning or eating foods that require a wide bite. Avoid applying cosmetics directly to the active lesion, as makeup can trap bacteria and irritate the sensitive area. If you apply makeup near the sore, discard any product, like a lipstick or brush, that has made direct contact with the blister to prevent reintroducing the virus.
Use gentle movements when washing your face or brushing your teeth near the sore to prevent accidental trauma. Avoid harsh facial scrubs or chemical peeling agents, as these can strip the protective layer of skin. Postpone any scheduled dental or cosmetic procedure until the cold sore is completely healed, as the trauma can worsen the outbreak.
External Factors to Limit During Healing
Exposure to environmental and dietary factors can prolong the healing process and increase discomfort. Ultraviolet (UV) radiation from sunlight or sunbeds is a known trigger for outbreaks and can irritate an existing lesion. If you go outside, protect your lips by applying a lip balm with an SPF of 15 or higher.
Extreme weather conditions, such as strong wind or intense cold, can cause the skin to dry out or crack, stressing the healing sore. Protecting the area with a barrier, like a scarf, helps maintain moisture and prevents the lesion from becoming painfully chapped.
Certain foods can irritate the open lesion and should be limited while the sore is active. Highly acidic items, such as citrus fruits, tomatoes, and vinegar-based foods, can cause a painful stinging sensation. Salty or spicy foods can also irritate the raw skin and increase local inflammation.