Cold sores are small blisters that typically develop around the lips or mouth. They are caused by the herpes simplex virus type 1 (HSV 1). Half of the world’s population (around 3.7 billion) are carriers of HSV 1, making it one of the most common viral infections globally.
What is a cold sore?
Cold sores (or fever blisters) often start out as a red patch around your mouth. Within a few weeks, they will begin to blister and turn white. After 1 to 2 weeks, you may notice a yellow crust forming on top of blisters which is a sign that they are healing.
Cold sores aren’t dangerous and usually go away all by themselves, but they can cause discomfort. You may also notice other symptoms such as fever, swollen lymph nodes, and fatigue.
Not everyone who carries the HSV 1 virus will have cold sores. Some carriers may never notice a herpes outbreak in their entire lives.
Fever blisters can show up anywhere on the body, like your knees, arms or torso.
Canker sore vs cold sore
It’s easy to mistake canker sores for cold sores, but they are not the same. The difference between cold sores and canker sores is that one is located on the outside of the mouth (cold sores), whilst the other will show up on the inside (canker sores). Canker sores are not caused by HSV.
What causes cold sores?
Cold sores are mostly caused by HSV 1, but herpes simplex type 2 (HSV 2) can also lead to open source and blisters surrounding the mouth. HSV 2 is a dominant cause of genital herpes, but recent studies show that people can get cold sores when performing oral sex with an HSV 2 infected partner.
If you carry HSV, you may not notice any symptoms. Cold sore outbreaks are more likely during times when your immune system is compromised, e.g. when you have a cold or flu
Cold sore prevention
What causes cold sores to flare up will be different from individual to individual. If you suffer from cold sores frequently, it’s best to try and prevent an outbreak. There are a couple of measures you can take that do not involve medication.
- Exposure to sunlight or tanning beds
- Extreme temperatures (hot or cold)
- Cracked lips
You can wear sunscreen and apply lip balm to make sure the skin on your lips doesn’t get damaged.
You should boost your immune system by maintaining a healthy balanced diet and exercising regularly.
If you currently have cold sores, you must protect yourself and others from spreading HSV, by:
- Not kissing others until the sores have completely healed
- Not sharing cutlery, toothbrushes or towels
- Disinfecting your hands after touching your lips
- Avoiding oral sex
- Parents of newborns should not kiss their babies because their immune system has not fully developed
Cold sore treatments
Cold sores tend to clear up without treatment after 2 weeks. But if your symptoms are painful or you are looking to get rid of a cold sore fast, here’s what you can do.
The fastest way to get rid of a cold sore is by treating it as soon as you notice any symptoms. You can apply an antiviral ointment 2 to 5 times a day. They are available over-the-counter at your local pharmacy or supermarket.
- Acyclovir (Zovirax)
- Penciclovir (Denavir)
You can also take antiviral oral tablets such as:
- Famciclovir (a dose of 1.5 g once)
- Valacyclovir (Valtrex) (take 2 g twice for one day, 12 hours apart)
Antiviral ointments do not prevent cold sores from recurring in the future even if you apply them every day.
If you get cold sores often and are in a relationship, long-term suppression therapy with valacyclovir has been shown to be effective in lowering your risk of spreading HSV 1 to your partner.
Unfortunately, there are no miracle cures for fever blisters. Although antiviral remedies work fast, none of them work in just 24 hours. Once you’ve developed blisters, they will take at least a few days to heal completely.
But there are a few home remedies you can try to reduce cold sore swelling:
· Support your immune system. A strong immune response is the most important component in the fight against cold sores. Take vitamins, eat healthily and find a good probiotic to support gut health.
- Kanuka honey. Applied five times a day, this honey from New Zealand has been shown to be just as effective as acyclovir cream in reducing cold sores.
- Propolis. Propolis is a component of bee pollen that may have some good antiviral properties. It is available as a supplement or as an ingredient in some cold sore creams.
- Lemon balm. There is some evidence that lemon balm ointment could be beneficial in speeding up the healing process.
- Lysine. Some research suggests that taking lysine regularly may result in fewer cold sore outbreaks. Supplementing with the amino acid may prove useful for some people to reduce the recurrence of cold sores.
- Zinc cream. There is evidence that zinc inhibits HSV 1 and HSV 2 virus from spreading.
Should I pop a cold sore?
It can be tempting to touch or pick at scabs and cold sores but doing so usually prolongs the treatment duration. Try to avoid touching, popping or picking at a cold sore or scab. Avoid acidic or spicy food because they can aggravate the skin.
If you experience severe pain, have cold sores very often or develop them near your eyes, consult a doctor.
- World Health Organization: WHO. (2015, October 28). Globally, an estimated two-thirds of the population under 50 are infected with herpes simplex virus type 1. Retrieved from Who.int website: https://www.who.int/news-room/detail/28-10-2015-globally-an-estimated-two-thirds-of-the-population-under-50-are-infected-with-herpes-simplex-virus-type-1
- InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-. Cold sores: Overview. 2018 Jul 12. Available from: https://www.ncbi.nlm.nih.gov/books/NBK525782/
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