The first line of defence is to boost your immune system - and here, complementary health really comes into its own with a combination of herbal, homeopathic, and nutritional steps to suppress the virus and keep it dormant.

Although a homeopathic constitutional diagnosis is always better in the long-term, if you are already on holiday and away from your homeopath when a herpes outbreak threatens, it makes sense to dose yourself homeopathically and support the system while its under attack.  If you tend to get cold sores in the sun and they start with that familiar itchy tingle, take the homeopathic remedy Natrum Mur 30c. If an outbreak begins with more of a sharp, prickling pain and the sore tends to crack and bleed, you need to take homeopathic Nitric Acid 30c. 

The cold sore virus is activated by an amino acid called arginine. Another amino acid called lysine inhibits the absorption of arginine and therefore helps suppress this virus. Foods that are rich in arginine (and which you need to avoid) include chocolate, nuts, and most cereal grains. Natural sources of lysine include dairy products, potatoes, and brewer’s yeast so step up your dietary intake of these and take a lysine supplement.

Zinc, which boosts the immune system, has also been shown to help. Food sources include oysters, seafood, eggs, liver, turkey, sunflower and pumpkin seeds - but if you plan to take more than 30mg a day for several months, you will need to balance this with a copper supplement of 2mg a day. (Note - Patients diagnosed with Alzheimer’s disease should not take zinc supplements until researchers have clarified the role of this mineral in the disease.)

One of the most potent and less well known antidotes to cold sores is St Johns Wort - or nature’s prozac - which is more usually taken for mild to moderate depression. It has fantastic antiviral properties and although reported side-effects include increases photosensitivity in sunlight, this has only been recorded among cows grazing on meadows of the herb.

In an emergency, and as soon as you recognise you’re feeling run down or you start to feel that dreaded tingle, rush out and buy a bottle of Echinacea tincture. Echinacea or Purple coneflower was widely used in the early 1900s before man-made antibiotics took over, but its powerful healing properties were first discovered by the Sioux tribe who used it to heal snake bites and accelerate wound healing. It’s now the best-selling immune booster both sides of the Atlantic, and its popularity soared when researchers found it could support the immune systems of seriously ill AIDS patients.

I always use Bioforce's tincture. Take 20 drops, three times a day, for about 10 days. It’s important not to over-use Echinacea, because it loses its potency if you take it daily for more than a fortnight.

If you cannot prevent an attack, you can still reduce the severity and shorten the time between the first tingle and healing by applying the natural antiseptic tea tree oil directly on to the affected area. Always test a small area of skin before applying the oil directly as some people may have an allergic reaction. Tea tree is now so popular we’re spoilt for choice with different brands. I always keep a phial of the Desert Essence brand, which seems to do the trick. Grapefruit seed has strong antibacterial and antiviral properties and is also safe to dab on the sore. If you suffer from recurrent sores, your immune system is compromised and needs supporting with herbs such as elderflower, astragalus, or liquorice.

With cold sores, prevention is the key and I have heard strong anecdotal reports of a wonder supplement called Elagen, in which the active ingredient is an Asian plant called Eleutherococcus senticosus. Related to ginseng, this is said to bolster the body’s natural defences. After Trading Standards litigation, the manufacturer was forced to withdraw claims that it could help cure cancer but the prosecuting lawyers did not dispute the suggestion that it is an effective immune enhancer and as such, can help keep the cold sore virus at bay.