Cold sores, also called fever blisters, are caused by the herpes simplex virus type 1 (HSV-1). Once infected, the virus stays dormant in nerve cells indefinitely and can reactivate later, causing painful blisters typically around the lips, nose, or chin. Reactivation is triggered by factors like stress, illness, hormonal changes, weakened immunity, or too much sun exposure.

Early symptoms often include tingling, itching, or burning before blisters appear. These blisters then burst, ooze fluid, and scab over, healing within two to four weeks. While cold sores usually clear up on their own, antiviral medications such as acyclovir and valacyclovir can shorten outbreaks when started early.

Over-the-counter creams with docosanol or lidocaine help relieve discomfort, while natural remedies like aloe vera, lemon balm, and tea tree oil may reduce inflammation. Keeping the area moisturized with petroleum jelly or lip balm prevents cracking and secondary infection.

Preventing outbreaks involves avoiding triggers: managing stress with relaxation techniques, protecting skin from sun exposure using SPF lip balm, and supporting immune health through a balanced diet, hydration, and adequate sleep. These steps can lower the frequency of flare-ups.

Cold sores are highly contagious and spread through direct contact with sores or sharing items like lip balm or utensils. Good hand hygiene and avoiding kissing or sharing drinks during active outbreaks are essential to reduce transmission.

Although there’s no cure for HSV-1, understanding symptom management, prevention, and transmission helps people live well with the virus. Medical advice is recommended for frequent or severe cases, and ongoing research is exploring vaccines and new treatments to improve care.