What exactly are cold sores? We spoke with a board-certified dermatologist to break down the facts about Herpes Simplex Virus (HSV), the cause behind cold sores, and how you can manage outbreaks with confidence.
What Is Herpes Simplex?
Herpes Simplex Virus (HSV) is a common viral infection that exists in two main forms: HSV-1 and HSV-2. Cold sores are typically caused by HSV-1, although HSV-2, more commonly associated with genital herpes, can also be responsible in some cases.
Once infected, the virus stays in your body for life. It tends to hide in nerve cells and can reactivate later, often during times of stress, illness, hormonal changes, or sun exposure — all common cold sore triggers.
What Does a Cold Sore Look Like?
Cold sores usually begin with a tingling, burning, or itching sensation around the lips or mouth. This is followed by the appearance of small fluid-filled blisters that eventually burst, crust over, and heal within 7 to 10 days. They can be uncomfortable and sometimes painful, but for most people, they’re more of a nuisance than a serious medical issue.
How Is Herpes Simplex Spread?
Cold sores are highly contagious, especially when the blisters are visible. HSV-1 spreads through close contact like kissing or sharing items like lip balm, razors, or eating utensils. It’s also possible to spread the virus to other parts of your body or to someone else, even when sores aren’t visible, through what’s called asymptomatic shedding.
How Can You Treat and Prevent Cold Sores?
While there’s no cure for HSV, several effective treatments can reduce the severity and frequency of outbreaks. These include:
- Antiviral creams or ointments, which work best if applied early
- Oral antiviral medications (like acyclovir or valacyclovir), often prescribed for more frequent outbreaks
- Lifestyle management to reduce triggers, such as using sunscreen on lips, managing stress, and getting enough rest
If you experience frequent or severe cold sores, a dermatologist can help tailor a long-term treatment plan to keep symptoms under control.
👩⚕️ Want to hear directly from the expert?
Watch our Dermatologist Explainer on Herpes Simplex (Cold Sores) to learn how to manage your skin and stop outbreaks before they start.
