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Herpes Labialis

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Herpes labialis also known colloquially as a cold sore or a fever blister, is a commonly occurring but infectious group of lesions occurring in the oral cavity.

Medically reviewed by

Dr. Sowmiya D

Published At April 8, 2022
Reviewed AtAugust 4, 2023

What Is Herpes Labialis?

This infection caused by the herpes simplex virus occurs mainly around the lips or within the oral mucosal membranes that spread primarily by orogenital contact, i.e., through kissing or unprotected sex and skin-to-skin contact like handshakes, hugs, etc.

The average incidence of this viral infection is approximately 1.6 per every 1000 patients in a year, and the prevalence rate is 2.5 per 1000 patients per year. Almost one-third of all infected patients usually suffer a relapse of the infection due to viral reactivation.

Herpes labialis is mainly characterized by skin rashes and mucous membrane rash, particularly prominent in or around the lips. This area has erythema or an inflammatory lesion-like appearance, and often it is not uncommon to notice blisters that are accompanied by pain and burning sensation.

It is essential to know that herpes labialis is a relatively harmless self-limiting condition but often remains a source of significant oral discomfort. This is more especially in immunosuppressive patients, though in immunocompetent cases, the lesions spontaneously heal within 7 to 10 days.

What Causes Herpes Labialis?

Herpes labialis is only contagious for individuals not previously infected by the virus. Also, it can be contagious in immunosuppressive patients or those patients with weakened immune systems due to underlying systemic infections, infections, systemic disease (like heart disease), cancer patients undergoing chemotherapy, etc. Herpes labialis infection can also additionally result in genital herpes through orogenital contact. Herpes labialis is caused by the pathogen herpes simplex virus type 1 (HSV-1).

Infection with type 2 HSV virus can also cause primary herpetic infections, but this type does not usually relapse. The primary infection with HSV-1 most commonly occurs below the age of 20 in young adults in most cases. Antibodies against the virus will be found in 80 % of the infections in adolescents and young adults. Recent studies by clinical research indicate an epidemiologic shift that is more common for the primary disease of HSV to manifest as genital herpes through an orogenital route or contact.

What Are the Clinical Features of Herpes Labialis?

The clinical symptoms mainly occur in young children presenting with primary herpetic stomatitis. They are characterized by fever and the formation of small blisters and ulcers orally ranging from approximately 2 to 10 mm, and they may involve the tongue or the lips. In Adults, the infection mainly presents with a sore throat and lymph node swelling vertically in the neck, strongly resembling or with a similar impression to mononucleosis.

Relapsing HSV infections are characterized by burning skin rashes and ulcerations or lesions on the lips and around the mouth or the oral cavity as either papules, vesicles, or crusty lesions. In HSV infection of adolescents, clinically, it frequently manifests as moderate to severe pharyngitis. The oral lesions are observable on the oral mucosal membranes, the cheek, or the gingiva.

In addition, patients may complain of difficulty swallowing (dysphagia) and swollen lymph nodes (lymphadenopathy), mainly in the neck. The differential diagnosis by the physician or dentist should thus include glandular fever or infectious mononucleosis as the manifestation of the clinical symptoms of both infectious mononucleosis and primary HSV remains almost similar.

What Is the Clinical Progression of Herpes Labialis?

After primary infection, the virus may be latent even after entering the trigeminal ganglion via the sensory nerve (where it lies latent potentially even throughout a lifetime). Trigger factors or stimuli such as chronic or acute fever, menstrual issues, hormonal fluctuations, exposure to sunlight for prolonged periods, and certain upper respiratory infections can reactivate the latent virus. This is when the triggers stimulate the epithelial cells via the sensory nerve. In primary infection of HSV, oral mucosa is undoubtedly affected; however, in relapsing infections orally, the lesions are either limited to the mucosa of the hard palate or the lips. The infectious relapsing capacity subsidies as per research after 35 years.

The clinical progression or the pathogenesis of this latent viral infection to activation or reactivation is through a series of eight phases that are elaborated below:

1. Latent Phase (May Last From a Few Weeks to Months):

This phase is the first stage characterizing the initial infection when the virus lodged itself within the sensory nerve ganglia, i.e., the (trigeminal ganglion). Here, they reside in an inactivated latent form that needs triggers or stimuli to undergo the progression clinically.

2. Prodromal Phase (Day 0–1):

Patients may complain of tingling (itching) and reddening or erythema of the infected skin. This stage may last or vary from a few days to a few hours.

3. The Phase of Inflammation (Day 1):

The activation of the viral pathogen further infects the nerve cells, and the healthy body cells create an immune defense by manifesting swelling and redness in the affected area.

4. Sore or Pre-Sore Phase (Day 2–3):

This phase is characterized by complex, inflamed papules or vesicles creating itching sensations, pain, and sensitivity to touch. These fluid-filled blisters may form a cluster on the vermilion border of lips or the area between the lip and skin, or even on the nose, chin, etc.

5. Phase of the Lesion (Day 4):

This is a contagious phase, and painful to the patient wherein the vesicular lesions merge to form large ulcers or weeping ulcers. This discharge is usually watery and filled with viral particles. The virulence of the activated pathogen is high in this phase.

6. Crusting Phase (Day 5–8):

A golden or brownish honey crust forms in this phase containing proteins and immunoglobulins, starting the repair or healing process. Though The sores may be painful at this stage, the scars of crusts cause oral discomfort to the patient even while talking and eating.

7. Healing Phase (Day 9–14):

Post-repair, the new skin begins to form underneath the existing scab as the virus again retreats into a latent inactivation phase.

8. Post-scab Phase (12–14 Days):

Erythematous areas may still linger at the site of infection, but the regenerated skin results in minor discomfort and pain for the patient. Virus shedding is a continuous process during this phase.

What Is the Management of Herpes Labialis?

Antiviral medications can be prescribed for topical applications for mild to moderate infections. In contrast, antiviral therapy by Acyclovir and Valacyclovir, along with Lysine supplements, can be started for recurrent infections of HSV. Exposure to sunlight should be avoided during this treatment phase as it can act as a potential trigger.

How Can We Prevent Herpes Labialis?

The prevention of the spread of infection is done by following strict measures and hygiene behaviors, including:

  1. Frequent handwashing.

  2. Following proper oral hygiene by brushing twice a day accompanied by regular mouth rinsing with antiseptic or antiviral rinses suggested by the dentist (ethanol containing rinses or essential oil mouth rinses are recommended therapeutically).

  3. The outbreak can be mainly prevented by avoiding contact for a few days with a disinfected individual either orally or genitally.


To conclude, herpes labialis is a commonly occurring and infectious yet self-limiting ailment but requires physician and dentist guidance and therapy to prevent physical discomfort and recurrent infections of the HSV virus.

Frequently Asked Questions


Is Herpes Labialis a Sexually Transmitted Disease?

Yes, herpes labialis (cold sores) is caused by the herpes simplex virus (HSV-1), which can be transmitted through skin-to-skin contact, including kissing or oral sex.


How Serious Is Herpes Labialis?

Cold sores and oral herpes labialis are two frequent viral infections that affect the mouth and lips. Although it is typically not seen as dangerous, people with it may experience discomfort and shame. In some circumstances, such as those with compromised immune systems, it can result in more severe problems. To lessen the chance of the virus spreading to others, it is critical to maintain proper cleanliness and stay away from direct contact with cold sores.


Will Herpes Labialis Infection Persist Lifelong?

Yes, herpes labialis, also known as cold sores or fever blisters, is a viral infection caused by the herpes simplex virus (HSV). Once infected with HSV, the virus remains in the body for life and can reactivate and cause outbreaks of herpes labialis. While outbreaks can be managed with antiviral medications and other treatments, there is currently no cure for the virus.


Is Herpes Labialis Treatable?

No, herpes labialis (or cold sores) caused by the herpes simplex virus (HSV-1) is a viral infection and is not curable. However, the symptoms can be managed and treated with medications to reduce the frequency and severity of outbreaks. In some people, the frequency of outbreaks may decrease over time. Good hygiene and avoiding triggers that cause outbreaks may also help manage the condition.


Can Herpes Labialis Spread From Person to Person Without Kissing?

Yes, herpes labialis, also known as cold sores, can be transmitted through other methods besides kissing. These include direct skin-to-skin contact, personal sharing of items like towels or razors, and sexual contact. It can also spread from an infected individual to other parts of their body, such as the eyes or genital area.


What Foods Should Be Avoided by People With Herpes Labialis?

Foods high in arginine, such as chocolate, nuts, seeds, and soy products, should be avoided with herpes labialis as they can trigger outbreaks. It's also recommended to limit the intake of other trigger foods, such as processed foods, coffee, tea, alcohol, and spicy or acidic foods, as they can irritate the affected area and worsen symptoms.


What Are the Trigger Factors for Herpes Labialis?

Herpes labialis is usually triggered by stress, sun exposure, fatigue, or a weakened immune system. Some other factors that may trigger an outbreak include hormonal changes, the cold or flu, and certain medications. Additionally, people with a history of herpes labialis may experience outbreaks when they come into contact with the herpes simplex virus, which is highly contagious.


Can Vaseline Be Applied to the Herpes Lip?

Vaseline can be used on herpes labialis, yes. Vaseline does not contain any antiviral characteristics to treat the herpes virus, so it is vital to remember that it is a physical barrier to stop the skin from drying out and cracking. For proper herpes labialis therapy, it is advised to speak with a healthcare professional.


For What Duration Do the Herpes Labialis Sores Stay on the Lips?

Lip herpes outbreaks, commonly referred to as oral herpes or cold sores, usually last from seven to ten days. Although outbreaks can last for a variety of times, some people may suffer longer or shorter outbreaks. Additionally, the frequency and intensity of outbreaks can differ from person to person and may be influenced by a number of variables, including immune system health, stress levels, and triggers like sun exposure.


Can Herpes Labialis Be Cancerous?

No, herpes Labialis is not associated with any type of cancer.  However, genital herpes can progress into cancer.


What Lotions Are Helpful in the Management of Herpes Labialis?

Various over-the-counter gels and ointments can treat herpes labialis, also known as cold sores. 
 - Among the often employed ones are:
 - Antiviral cream
 - Cream for penciclovir
 - Docosanol lotion


What Is the Best Medication for Herpes Labialis?

Antiviral drugs, including acyclovir, valacyclovir, and famciclovir, are the most effective treatments for herpes labialis (cold sores). These drugs can lessen the length of an outbreak, the intensity of the symptoms, and the chance that it will spread to other people. As soon as symptoms develop, you should start taking the prescription because it works better if you do. These drugs are accessible with a prescription from a medical professional and can be used topically or orally.


How Will Herpes Affect Individual's Lives?

Herpes can significantly impact a person's life, including
 - Physical Discomfort: Outbreaks of herpes can cause pain, itching, and burning sensations.
 - Emotional Impact: Herpes can lead to anxiety, depression, and reduced self-esteem.
 - Social Stigma: A significant stigma is often associated with herpes, leading to social isolation and shame.
 - Reproductive Health: Women with genital herpes may experience complications during pregnancy, including the risk of transmission to the baby.
 - Sexual Health: Herpes can make sexual activity painful and limit the number of sexual partners a person may have.
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Dr. Achanta Krishna Swaroop
Dr. Achanta Krishna Swaroop



herpes simplex virus
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