Cold sores (herpes labialis) are small fluid- filled blisters that usually form on the lips or skin around the mouth, nose and on the chin. They are caused by infection with the herpes simplex virus (HSV) type 1, which is transmitted through close skin-to-skin contact with saliva or direct contact with a blister e.g. through kissing.


People are usually infected with HSV in childhood or early adulthood, and the infection persists for life. About 90% of Australians carry the HSV-1 virus, but only a third of infected people experience cold sores. Symptoms don’t usually occur at the time of the first infection (primary infection) which means when the cold sores do develop, they are not usually as a result of catching the infection for the first time. Because cold sores cannot be totally eliminated by the body’s defences, they often recur.


Symptoms of cold sores occur two weeks after initial contact. The herpes virus doesn’t leave the body; it lies dormant in nerve endings until triggered.

First signs that a cold sore is imminent include localised itching and tingling. Within hours to days, a small fluid-filled blister appears which can be accompanied by pain, tenderness and a sensation of heat and burning. These blisters burst after a few days leaving a tiny round ulcer/crust, which will dry up and eventually fall off after about 10-14 days. Primary infections can also be accompanied by fever and flu-like symptoms (sore throat, swollen neck glands, tiredness).

Common triggers of cold sores include emotional stress, trauma or bumping to the area, exposure to wind and sunshine and infection, such as colds. In women, outbreaks often occur prior to menstruation.


While recurrent cold sores usually appear in the same place and don’t require treatment, complications may occur in people with weakened immune systems who may experience more severe symptoms that require medical care.

In these cases, the cold sores may become infected with bacteria. Possible symptoms include redness around the blisters, pus in the blisters and fever. Or may spread to other areas of the body such as they eyes (where it can damage eyesight), skin, or genitals (where it can lead to genital herpes). Permanent damage can usually be prevented by early treatment, including medication to suppress the virus.


Because cold sores are easily spread, people with the infections should wash their hands often, especially after touching their cold sore. They should avoid sharing eating utensils, toothbrushes, drinking glasses or bottles, towels or other personal items. They should also avoid close contact (such as kissing and hugging), especially with newborn and young babies, children with burns or eczema, or people with suppressed immune systems.


Cold sores are generally not dangerous and do not cause any permanent damage to the skin. Treatment does not cure the infection and is not necessary for most cases. Avoid picking the scab or breaking blisters as this can cause secondary infection and scarring.

Antiviral medications come in many forms, including creams and tablets. Medications such as acyclovir and famciclovir shorten the duration of the cold sore by reducing the ability of the virus to reproduce. Aciclovir cream (e.g. Zovirax, Blistex Antiviral Therapy) works best when applied to the blister at the earliest stages of cold sore development, when the area is tingling. However, not everyone experiences warning signs of an impending cold sore.

Simple painkillers may occasionally be required and creams to treat the symptoms can be soothing. Povidone-iodine formulations (e.g. Betadine Cold Sore Paint) can be dabbed onto the cold sores and may reduce symptoms in some people, especially if applied at the first signs of a cold sore. Non-medicated patches (e.g. Compeed Invisible Cold Sore Patches) provide an optimal healing environment for cold sores sheltered from the elements to hasten the healing process. Herbal topical liquids (e.g. Dynamiclear Rapid) hasten the crusting process and reduce cold sore blisters with less redness and pain.

Other dietary and supplement measures that can be followed that can help with the treatments and prevention are:  


* Vitamin C (e.g. Lifestream Natural Vitamin C, Bio C, Cenovis Mega C) – A powerful antioxidant that helps to boost immunity and is anti-viral. Take 3-4g of Vitamin C a day and include Vitamin C rich foods in your diet.  

* Zinc (e.g. Bio Zinc, Ehical Nutrients Zinc Fix–Enhances immunity and reduces frequency and severity of herpes outbreaks. Take 50mg of zinc daily and eat zinc rich foods such as fish, dairy, egg yolks and legumes   

* Arginine- Reduce arginine-containing foods such as nuts, oats, turkey, chocolate and wholewheat. The amino acid arginine promotes cold sore outbreaks  

* Lysine (e.g. Ethical Nutrients Lysine, Lyp-Sine) – The amino acid lysine reduces viral replication and helps prevent cold-sore outbreaks, so eat plenty of lysine-rich foods such as legumes, fish, lamb and dairy. Alternatively supplements can be taken as a daily dose of 500mg for prevention, or three times a day to reduce symptoms.  

* Immune-boosting foods – Eat plenty of immune-boosting foods such as spirulina, green tea, Echinacea and shitake mushrooms  

* Caffeine Reduce caffeine intake as it over-stimulates the nervous system. The herpes virus lives in the spinal cord and travels along certain nerve paths, resulting in a breakout in the corresponding area on the skin.


There is no cure for cold sores, however preventative measures can reduce the number of outbreaks. Preventative measures include, keeping your face out of strong sun or wind, wearing sunblock on the face and lips while outdoors, maintaining good health and low stress levels.