Efudex: A Probable Culprit in Mystery Outbreak

When I first got a sore on my lip, I didn’t know what it was, but I was certain that the itching and burning were causing great distress.

It got worse when more spots popped up, spreading not only on my lip but on top and over and down like a mustache.

One night it itched so much that I had to take Benadryl. Another I was in such pain that I took oxycodone.

Cold sore or Efudex?

I thought it might be related to two things. One, I thought maybe a stray bit of Efudex had gotten on my lip when I applied it to possibly precancerous spots on my nose, temple, and neck. Two, I had decreased my dosage of Valtrex, an anti-viral that I take. The last time I cut back, I was tormented by a cold sore that ran across the whole top of my lip.

I looked up, “Can cold sores spread to your skin?” The answer was yes.

I sent photos to my dermatologist. She said she would see me.

Sending photos to my doctor

But first, I wasn’t going to let my discomfort stop me from a much anticipated trip to the US Open Tennis Tournament in Flushing, N.Y.

Up in the stands in Arthur Ashe Stadium, during a changeover in Raphael Nadal’s match against Nikoloz Basilashvili, I emailed a member of my team at Dana-Farber. No matter what dire circumstances I was in during treatment for leukemia, this infectious diseases doctor made me smile.

I wrote,

“Something weird has happened to my lips and I wonder if something broke out because I decreased the Valtrex but also wondering if by accident I got some Efudex around my lips or on then.

There is a little sore on my bottom lip and the rest of both lips are red and burning even onto my skin.”

He wrote back in less than 10 minutes, pretty fast for a doctor.

“Hi Ronni!

You could have burned the lip with the Efudex, but could also be HSV (herpes simplex virus). As you at are the open, I see no harm going up on the Valtrex dose for a few days.

Send a selfie with Nadal!”

I replied, “He’s too far away. I tried to take a photo of my lip but it was too gross.”

He wrote back: “Tell him to come over for the selfie.”

I wrote that I couldn’t since he was losing and in a bad mood... though he did eventually pull it out.

I said, “Couldn’t get Nadal but got Roger,” and I sent a photo of my friend Donna and me with a cutout.

I asked what to do in the meantime. He said nothing crazy, just some lip balm.

Grateful for quick responses from my medical care team

The next week when I went to Boston, my dermatologist confirmed that it was indeed a rampant cold sore, or herpes simplex. “You poor thing, you look so miserable,” she said.

I’m still not sure what role the Efudex played, but I didn’t understand how potent it is, and how many side effects it has, until I read the posts by April Pulliam on this site.

I slathered on Vaseline, stopped the Efudex, and increased the Valtrex. It eventually subsided.

The dermatologist’s kindness and the infectious disease doctor’s sense of humor, and the knowledge that his quick response meant he cared, also helped.

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