Because stress puts pressure on your immune system it acts as a trigger for the cold sore virus. So remember that it's the times when you least need a cold sore that you most need to keep Zovirax antiviral cream handy.

UV rays

Strong sunlight or ultraviolet (UV) light is another trigger for cold sores. So next time you're out in the sun, take extra care, use a sunscreen and keep some Zovirax cream handy. And if you're going on a holiday and you're prone to cold sores then it's good idea to take some with you.

Wind & Cold

Winter can be the worst time of year for cold sores. Wrap up well, and try to avoid that chilly wind-burn on lips. If you're going skiing, make sure you pack some Zovirax cold sore cream.

Lack of sleep

Lack of sleep can affect your immune system. So the less sleep you get the greater the chance for the cold sore virus to be activated. This can be a real problem for Mums of small children. Click here to see how wearing a Zovirax invisiSeal patch can help protect your children if you do get a cold sore.

The common cold

As the name suggests, if you're run down with a cold or flu or other infection, it's the perfect cue for the cold sore virus to activate. So if you're in the pharmacy or supermarket stocking up on cold and flu remedies it's a good idea to stock up on Zovirax antiviral cream at the same time.


If you ever bump, burn or bash your lips they can become more vulnerable to the cold sore virus. Damage aggravates your immune system and can trigger a cold sore.


The cold sore virus can be more active around your monthly periods. If you've noticed this pattern then at least you'll know when it's time to check your supplies of Zovirax cream.


That blue line's like a green light for cold sores. Whether you feel blooming marvellous or just plain terrible, all those changes and stresses are a great opening for the virus that triggers cold sores.

Zovirax invisi-Seal patches discretely cover the blister and reduce the risk of the virus spreading to your loved ones, especially babies and toddlers.

Zovirax Cold Sore Cream is not recommended for use in pregnancy.