What are cold sores?

Cold sores are small fluid-filled blisters which usually appear on the lips or around the mouth. After the blisters dry , they generally heal without leaving a scar. They are contagious from the moment symptoms such as tingling, or itch appear. Cold sores can  spread via direct skin contact or exposure to the saliva of an infected person.

What are the possible causes of this condition?

Cold sores are mostly caused by an infection with the Herpes Simplex Virus (HSV). Once infected with the HSV, the virus remains in the body for life. Cold sores may not appear again if the HSV remains inactive. However, the HSV may become active and cause cold sores via the following triggers:

• Exposure to strong sunlight, cold or wind
• Stress or fatigue
• Weakened immune system
• Fever or infection
• Hormonal changes (e.g. menses)

What are the symptoms of cold sores?

The symptoms of cold sores can include the following:

• Tingling, itching, or burning sensation around the lips a day before blisters appear
• Pain where the cold sores appear
• Blisters which ooze and crust over before healing

In the first outbreak, other  symptoms may include:

• Fever
• Sore throat
• Headache
• Painful gums
• Muscle aches

If cold sores occur again, they tend to appear at the same spot, and often are less severe than the first outbreak.

What can I do to treat cold sores?

Cold sores can be treated in the following ways and you can approach your pharmacist to get the following medications. 

• Anti-viral cream (e.g. Aciclovir) to treat the viral infection
• Pain relief oral gel (e.g. Choline salicylate) to help reduce inflammation and pain
• Anaesthetic spray or gel (e.g. Lignocaine, Benzocaine) to numb the skin 
• Pain or fever relievers (e.g. Paracetamol or Ibuprofen tablets or liquids)

When do I need to see a doctor?

Although cold sores can be treated without a doctor’s consultation, there are times where the condition might be more serious. 

If your condition does not get better in 2 weeks or gets worse, you should see a doctor. You should also see a doctor if you experience any of the following:

• Signs of infected cold sores (e.g. pus and fever)
• Severe symptoms (e.g. pain)
• Increased frequency of cold sores outbreak
• Cold sores have spread near to the eyes

What else can I do to manage this condition?

Other than using medications to treat the condition, cold sores can also be managed by the following methods:

• Apply lip balm containing a sunblock, to prevent a cold sore from cracking 
• Apply a cool compress on the blisters to soothe symptoms
• Keep cold sores clean and dry
• Avoid licking or picking the cold sore
• Get sufficient rest

The following are some suggestions to prevent cold sores from happening again:

• Avoid intimate physical contact e.g. kissing someone with a cold sore
• Do not share utensils or personal items such as towels, lip balm or razors with someone who has a cold sore
• Try to minimize known triggers e.g. apply lip balm with sunblock if sunlight is a trigger

Disclaimers
This article is jointly developed by members of the National Medication Information workgroup. The workgroup consists of cluster partners (National Healthcare Group, National University Health System and SingHealth), community pharmacies (Guardian, Unity and Watsons) and Pharmaceutical Society of Singapore. The content does not reflect drug availability and supply information in pharmacies and healthcare institutions. You are advised to check with the respective institutions for such information.

The content above is solely for informational purposes only and is not intended as a substitute for the advice provided by your physician, pharmacist or other healthcare professional. You should not use the information for diagnosing or treating a health problem or disease, or prescribing any medication or other treatment. Always speak with your physician, pharmacist or other healthcare professional before taking any medication or supplement, or adopting any treatment for a health problem.
 

Last Updated 12 June 2024