Cold Sores

What are the triggers of a cold sore? And what can I do?

4 min read
What are the triggers of a cold sore? And what can I do? What are the triggers of a cold sore? And what can I do? What are the triggers of a cold sore? And what can I do?

Once you get the herpes simplex virus 1, it cannot be cured but it can be managed. And you can help prevent the reactivation of the cold sore virus by identifying your triggers. Most people who are infected with the virus have no symptoms until some external factor wakes up the infection.

Reactivation of virus

Once you contract the HSV-1, it usually causes an initial outbreak of cold sores. Then the virus remains in your body for the rest of your life. However you will not get a cold sore while the virus lies dormant in the body between outbreaks. Many factors can wake up the virus which in turn, starts replicating and spreading. At the same time, the immune system tries to fight back the virus and this results in inflammation (pain and redness).

What are the triggers?

After you have contracted the virus, it remains inactive most of the time. However, every so often, the virus can be re-activated by certain triggers, resulting in an outbreak of cold sores. These triggers are of two kinds:

Linked to a personal condition

  • Illness: fever, flu, or cold
  • Trauma and stress including physical strain and emotional stress
  • Fatigue or lack of sleep
  • Hormonal changes, especially from menstruation or taking birth control pills
  • Minor injuries such as cracks in the lips
  • Weakened immune system due to unhealthy lifestyle (smoking, alcohol, and poor nutrition) or certain medicines such as chemotherapy


Linked to outdoor conditions

  • Excessive sun exposure: sunlight and artificial UV light
  • Skin exposure to extreme weather conditions (heat, cold or wind)

Measures of prevention

Most of these potential triggers cannot be completely avoided, or are difficult to avoid. But you can try to alter your habits to reduce the risk of re-igniting the virus.

Managing your stress by playing sport, practising meditation and yoga or simply by taking time for yourself are just some of the ways to try to avoid new flare-ups.

When the seasons change, your lips can dry out very quickly and become cracked. Hydrating them with a balm is the best defence against chapped lips. If sunlight triggers your cold sores, a sunblock lip balm (SPF 15 or higher) could be helpful.

Knowing yourself well

Knowing and recognising your triggers is a huge asset in managing outbreaks. To do this, it can be helpful to keep a journal where you record your stress level, the events that mark your daily life, what you eat, how you sleep, etc. Identifying the events that trigger new outbreaks will allow you to be proactive in preventing them in the future.