What Are Cold Sores (and Why Do They Love Surprising You)?
Cold sores rank among the most unpleasant viral skin infections out there. While they might not leave you bedridden, they still manage to affect a large part of the population and, let’s be honest, they have a knack for appearing right when you’re about to do something important—your big meeting, a first date, or that vacation you’ve been planning for months.
The culprit? Herpes simplex virus type 1, or HSV-1. According to France’s national health insurance (Assurance maladie), around 90% of French adults carry this virus, which typically settles in somewhere on your face and often makes its first appearance during childhood. After causing a mild inflammation, the virus likes to take a nap in a nerve ganglion—and it can wake up at any time, leading to the dreaded cold sore.
Is Fever Really to Blame?
Despite what its name suggests, a “cold sore” doesn’t necessarily show up because you’ve got a fever (sorry to disappoint). The reality is a little sneakier: cold sores can appear at any time, and often it’s not your body’s temperature that’s to blame.
“It’s true that when you have a fever, you can get a cold sore, but there are other things that help trigger them: stress, tiredness… Sometimes it’s sun exposure, and for women, it can even happen during menstruation,” said Dr. Vincent Valinducq on the TF1 morning show, Bonjour ! La Matinale.
So, cold sore triggers are more varied—and sneakier—than you might expect.
What Actually Triggers Outbreaks?
As Dr. Valinducq points out, there’s often more than one culprit behind a cold sore’s untimely arrival. Some of the main triggers include:
- Fever: Yes, it can be the traditional trigger, but there’s more to the story.
- Stress: That looming deadline or big presentation? Prime time for a cold sore attack.
- Fatigue: Burning the candle at both ends can wake up the sleeping virus.
- Sun exposure: For some people, a day at the beach can end with a not-so-glamorous souvenir on the lip.
- Menstruation: Hormonal changes can sometimes bring on an outbreak for women.
The takeaway: to avoid flare-ups and respond effectively, Dr. Valinducq recommends trying to pinpoint what sets off your own cold sores.
“I have patients who tell me it’s the sun. In those cases, they use a lip balm that shields them from UV rays to keep outbreaks under control,” he continues.
How to React Fast—and Stop Cold Sores in Their Tracks
So, what’s the secret weapon against cold sores? According to the good doctor, acting quickly is your best ally. As he explained in a previous episode of the show:
“So, when you feel it coming, you can feel that heat—what can you do? You react right away. You really need to take action before it appears, before it starts to bother you, you really need to act now.”
He adds:
“You have at your disposal, over the counter in your pharmacy, a small topical cream that can help if you recognize the symptoms early.”
And don’t forget: you can always make an appointment with your doctor, who can prescribe an antiviral treatment if you start it within 72 hours.
