A blister or clump of blisters around the mouth, which erupt into a sore. They are caused by the herpes simplex virus which lies dormant, and is activated by sudden exposure to hot or cold weather, exposure to direct sunlight or viral infections. Low immunity and stress may trigger an eruption.

Treatment - Practical Advice

Keep the sore clean and dry to prevent infection with bacteria. Your toothbrush may carry the virus. Once the blister has formed, change your toothbrush. Change it again once the attack has cleared up. Use a potent sunblock lip salve to protect from the harmful effects of the sun.

Dietary

Studies have shown that the amino acid L-lysine may help reduce the frequency and severity of cold sores. L-lysine is found in kidney beans, split peas, corn and wheat. The herpes simplex virus thrives off arginine, found in nuts, chocolate and seeds, so avoid these foods. A diet which incorporates wholegrain cereals, low fat dairy produce and meat, fish, and plenty of vegetables and fruit is essential to resist infection.

Aromatherapy

Geranium oil applied externally to cold sores every hour reduces pain and accelerates healing. You could also try eucalyptus.

Homeopathy

Take 1 tablet, 3 times daily as soon as the blisters start to develop. Continue dosage for up to 4 days:

Deep cracks in dry, burning lips with several blisters, or when provoked by sea air: Natrum muriaticum 6c. When not provoked by sea air: Rhus toxicodendron 6c.

Orthodox

Idoxuridine and acyclovir are two commonly used antiviral areas as soon as symptoms begin. They will not cure the outbreak on the lips, but will reduce the duration and severity of the attack.