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Cold sores: How do I manage this lifelong condition?

Even when you recover from cold sores, the virus will stay in your body’s system. Here’s how to manage it.

Cold sores are a small cluster of painful blisters filled with fluid that occur over your face or mouth. Also known as fever blisters or herpes simplex labialis, these sores usually start with a tingling, burning, or itching sensation around your mouth, especially on the lower edges of your lip.

It is estimated that nearly two-thirds of the world's population under the age of fifty have the extremely infectious herpes simplex virus that is responsible for cold sores around the mouth.

So, what causes cold sores?

Cold sores are caused by herpes simplex virus (HSV). There are two types of herpes simplex virus — HSV Type 1 and HSV Type 2. Previously, HSV type one was solely responsible for cold sores whereas its counterpart, HSV type two was responsible for genital herpes. However, as a result of changes in sexual practices, the type of herpes simplex virus no longer influences the location of lesions.

It is important to note that the herpes simplex virus is usually transmitted via body secretions. For example, HSV Type 1 can be transmitted through kissing. However, oral to genital secretion can also happen through oral sex. This implies that an individual with cold sores can potentially transmit HSV Type 1 to their partner's genitals, leading to genital sores. Persons with HSV are most contagious when they have cold sores, but are still highly infectious even when they have no blisters or sores.

Progression of cold sores symptoms:

As earlier mentioned, cold sores often begin with a burning, itching, or tingling sensation over the affected region. Over the next two days, small blisters fluid with fluid will appear in the affected area, usually over your mouth or facial region. As days elapse, your blisters will burst, crust and scab over gradually. They usually take approximately ten days to heal.

Recurring cold sores and potential triggers:

The associated cold sores' symptoms will eventually disappear, but the virus will continue to live in your body's nervous system. Occasionally, it will reappear, resulting in a recurring breakout of cold sores when triggered. Some of the most common triggers of recurring cold sores include a compromised immune system, insomnia or inadequate sleep, being unwell, stress, UV light exposure, and perhaps menses.

It is important to mention that while some individuals experience frequently recurring cold sores around two or three times annually, others may experience only one cold sore episode and never have another. On the other hand, some people never experience cold sores at all because the virus never becomes active.

Contagious period of cold sores:

Cold sores are usually highly infectious from the time of occurrence of burning or tingling sensation when the rash is present as well as when the sore has entirely dried and healed.

What treatment options are available for cold sores?

Unfortunately, HSV infections are lifelong. This implies that there is no cure for herpes simplex virus. Once you become infected, the virus will remain in your body forever. However, there are a variety of antiviral drugs that can be administered to help alleviate your symptoms, minimize the severity of the symptoms, and potentially shorten the course of infection.

In Singapore, the available treatment options may include:

  • Oral antiviral drugs.
  • Creams: To help relieve the associated pain and discomfort.

If the cold sores affect your daily life in one way or another, you should seek immediate medical attention.

If you are experience recurring episodes of painful cold sores or think that you could potentially transmit the virus to your loved ones, consider speaking to your doctor who can prescribe suppressive oral antiviral medication. Once you start this treatment, you will take daily oral antiviral drugs for some months to minimize your level of infectivity as well as your risk of transmitting the virus to those close to you.

I have contracted cold sores, what should I do?

If you have cold sores, the best thing you can do is to seek immediate medical intervention. However, bearing in mind that there is no permanent cure for cold sores, there are a couple of things you can to ensure you live a normal life. These may include:

  • Make sure you take a soft, cooling diet that will help soothe the affected area.
  • Always practice good hand hygiene both before and after applying the numbing cream onto your lesion.
  • Never kiss anybody when you have a cold sore.
  • Avoid all the potential triggers of cold sores.
  • Don't share anything that can potentially be in contact with a cold sore, including lipstick, creams as well as cutleries.
  • If UV light triggers your cold sores, you can consider using a lip balm with sunblock.
  • Don't touch your cold sores unless you are applying the medication.
  • Don't engage in oral intercourse until your cold sores are completely healed.

Cold Sores FAQ:

What can trigger a cold sore?

Some of the factors that are believed to trigger cold sores outbreaks include:

  • Strong sunlight.
  • Increased fatigue and tiredness.
  • Psychological or emotional stress.
  • Having an underlying infection, such as a respiratory infection.
  • Fever.
  • An injury to the affected area.
  • Strong UV rays.

What can be mistaken for cold sores?

To confirm if you are indeed having cold sores, you should always consult your doctor who will further assist you. Common cold sore symptoms to look out for usually include a tingling, numbing, itching or burning sensation around the mouth, the appearance of small watery-filled blisters, weeping ulcers, ulcers that scab over and fall off with time among others. Without treatment, cold sores typically last about ten days. However, some conditions are usually mistaken for cold sores including:

Canker sores
These are not caused by the herpes virus or any other known virus. Though their primary cause remains a mystery, they can be triggered by a minor injury to your mouth, an allergy, stress, food intolerance, or a vitamin B deficiency. They usually appear as small, oval, or round whitish sores with a red border and occur inside your cheeks, gums, or inside your lips. However, unlike cold sores that typically occur outside your mouth, canker sores only occur inside the mouth. Like their cold sore counterparts, canker sores are recurrent but are not contagious.

Ingrown hairs
These occur when your hair curls around and grows back into your skin, causing red spots that can turn into painful sores.

Contact dermatitis
This refers to a skin condition that results in red, itchy, dry, cracked or scaly skin, a rash or blisters. Like herpes, it recurs. While it is not an STD, it can be easily mistaken for herpes, especially when it appears in the genital area. But unlike cold sores, contact dermatitis can appear nearly anywhere on your skin and it is not caused by a virus.

A pimple
This is usually caused by hormonal changes, blocked pores, certain drugs, smoking, and allergy reactions among other things. It is worth noting that oral herpes is typically associated with more pain and itchiness than acne.

This is an extremely contagious skin condition that is quite common, especially among children. It causes large fluid-filled blisters that can appear all over the body.

How long will a cold sore remain contagious?

As previously explained, cold sores will remain contagious from the time of occurrence of the symptoms until they completely go away, which may take approximately two weeks.

Can you get cold sores from stress?

Stress is one of the known common triggers of cold sores. However, it should be noted that stress will only cause cold sores in an individual who is already infected with the herpes simplex virus. When you are stressed, your body's immune system resistance to the virus isn't very strong, implying that the virus has the chance to break out one more time.

How do you kill a cold sore before it attacks?

The surest way to kill off the herpes simplex virus before it starts is to seek immediate medical attention and start taking the prescribed antiviral medication as soon as possible.

What will happen if I don't treat my cold sores?

Even though cold sores are usually very mild, they can potentially result in complications, especially if left untreated. It is also worth noting that those with compromised immune systems are particularly at a higher risk of complications. The herpes simplex virus can potentially spread to other parts of your body, resulting in skin infections; herpetic whitlow, a viral condition which causes painful blisters and sores to appear around your fingers; and herpetic keratoconjunctivitis, an infection of the cornea which causes irritation and swelling around the eye region. If left untreated, herpetic keratoconjunctivitis can affect your cornea, potentially leading to blindness.


  1. Cunningham, A., Griffiths, P., Leone, P., Mindel, A., Patel, R., Stanberry, L., & Whitley, R. (2012). Current management and recommendations for access to antiviral therapy of herpes labialis. Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology53(1), 6–11. https://doi.org/10.1016/j.jcv.2011.08.003
  2. Richardson, V. N., Davis, S. A., Gustafson, C. J., West, C. E., & Feldman, S. R. (2013). Patterns of disease and treatment of cold sores. The Journal of dermatological treatment24(6), 439–443. https://doi.org/10.3109/09546634.2013.789476

This article was written and medically reviewed by Dr Ben, M.D on 18/04/2021

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