Herpes labialis

What are the causes of herpes labialis?

Herpes labialis, commonly known as cold sores, is a type of infection by the herpes simplex virus. Approximately 90% of the adult population have had an herpes labialis infection at some point in their lives, but not all experience any symptoms. The virus does not leave the body, however, and it can cause occasional symptoms.

Symptoms of herpes labialis: redness and blisters

The typical initial symptoms of herpes labialis include redness and a burning or stinging sensation in the lips and oral mucosa. A couple of days after the appearance of these symptoms, blisters develop on the lips. The blisters are initially clear before first turning yellow and then developing into watering scabs. The scabs fall off in a week or two.

A herpes labialis infection can also spread to other parts of the face than the area of the mouth and lips. A quite common location of herpes labialis is next to the nostrils. If the herpes symptoms spread near the eyes, it is advisable to seek the attention of an ophthalmologist.

The virus is asymptomatic most of the time, but it can be activated by the common cold, sunshine or stress, for example. There is no way of preventing a herpes labialis infection, and it is not worth placing certain restrictions on your life.

Treatment of herpes labialis

Herpes labialis is most commonly treated with aciclovir or valaciclovir. If the infection is intense, orally taken aciclovir or valaciclovir provide quick relief. Herpes subsides spontaneously in a week or two.

When should you see a doctor?

It is recommended to seek medical attention in the case of prolonged symptoms of herpes. You should also see a doctor if you are experiencing the symptoms of herpes labialis for the first time. It is recommended that a doctor confirms that the symptoms are related to herpes labialis before treatment is initiated.
If the blistering area becomes suppurative or purulent, visiting a doctor is recommended. A bacterial infection may develop in the suppurative blistering area. The doctor will then assess if the area needs to be treated with an antibiotic cream or an antiseptic hydrocortisone cream.

If the herpes recurs frequently, a doctor may prescribe a prophylactic medication. Prophylactic treatment includes a small does of aciclovir or valaciclovir.

You may book an appointment with a dermatologist, a general practitioner or your occupational health physician.

Pharmacological treatment of herpes labialis

The most commonly used medications for herpes labialis are aciclovir or valaciclovir. They are antiviral medications. Aciclovir creams and valaciclovir tablets are available in pharmacies without a prescription.

Transmission of herpes labialis

It is easy to transmit herpes labialis through skin contact. That is why unnecessary touching of the infected area during an active infection should be avoided, the hands should be washed extra carefully and good oral hygiene should be maintained. The area where the symptoms are present should be kept as clean as possible.

If you have an active herpes labialis infection, you should not visit a dentist or any another oral healthcare professional.

Herpes and pregnancy

Some women experience more symptoms of herpes during pregnancy. If the herpes is located in the genital area, it should be reported to the staff of the child health clinic as soon as the pregnancy is confirmed. Herpes labialis cannot be transferred to the foetus because the virus has not entered the circulatory system.

Herpes labialis in children

Children can also become infected with herpes. Most children experience the first symptoms at the age of 3–5. Children under 3 with the herpes virus can experience inflammation of the mouth and lips (stomatitis), which may also include a minor fever. Children with symptoms should always see a doctor.

Text: Expert interview with dermatologist Maarit Vaalamo.

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