Herpes virus and cold sores – what to do?

My grand daughter (13 yr) gets cancer sores ( herpes simplex) sometimes when her monthly acne symptoms appear. I know she is probably sick of me repeating the content of you amazing web page to her, but I will do it anyway. Is lip sunscreen of any help? I told her that I thought she should toss the sunscreen because of the possibility of contaminating the lip sunscreen? have I got this correct? What's best for lip moisture when she has a bad breakout? I don't see this addressed anywhere.

Many people suffer from these outbreaks and they can be controlled usually. Remember that sores inside the mouth are “cancer sores” and they are different. The herpes virus on the lips is on the lips themselves but can occur in many different places like the nose, and even body sites sometimes.


Sunlight can activate the herpes virus so lip sunscreen is helpful!  Generally, don’t let her friends use the same lip sunscreen but it’s fine for her to use it. The cold sores creams sold in drugstores really don’t work very well. What works are several well tested and quite safe prescription medication taken twice a day for several days at the first sign of a breakout. Please see her pediatrician and have him/her prescribe it for her. The most commonly used ones are Valtrex (valcyclovir), Famvir (famcyclovir) and acyclovir.  She will be amazed at how well these work.


Hope this helps,  Dr. I


See the best skincare products for sun protection.


Read Dr. Irwin’s article on Skin Care Terms and Ingredients.



Dr. Brandith Irwin, MD

Ask me your skincare question!

Hi, I’m Dr. Irwin. I believe that consumers deserve a medically trained and unbiased skin care advocate.

  • All our content is written and researched by myself.
  • My medical office in Seattle has treated thousands of patients for 15+ years.
  • This site is not affiliated or financially tied to any product, treatment or device.
Ask Me Something
SkinTour Skincare
One of the best investments in your skin is your daily skincare. Why? Because you can prevent many problems with blotchy skin color, lack of glow, texture, some types of acne, and fine lines with good skincare products. You can also correct some of these problems with effective skincare products. Great skincare is often more expensive because quality ingredients are expensive. Some companies spend on research/development which benefits all of us and adds to the cost. Are they worth it? In general - yes! I have handpicked some of what I consider to be the best skin care products, and offer them for sale on SkinTour's shop. This is based on my team and I's testing and research at our clinic. Many of the products are in my own regimen. What could be better than using skin care products a dermatologist uses?!