The Difference Between Lip Blisters And Cold Sores

Have you ever had a blister lingering on your lips and wondered what it is and where it came from? Lip blisters can sometimes be annoying and uncomfortable because of the burning, itching, or tingling sensation that accompanies them. Moreover, there are various types of lip blisters depending on their location and cause. 

People often use the terms lip blisters and cold sores interchangeably. But are lip blisters and cold sores the same thing? Read on to learn about the difference (if any) between lip blisters and cold sores, the various causes of blisters on the lips, and treatment options.

Have you considered clinical trials for Cold sores?

We make it easy for you to participate in a clinical trial for Cold sores, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

What are cold sores?

Cold sores are tiny red fluid-filled blisters that appear near the mouth and lips during the initial stages of their infection. Though rare, cold sore blisters from the same virus may form on the nose, fingers (herpetic whitlow), or inside the mouth. Cold sores are also called fever blisters. 

Cold sores stem from the herpes simplex virus. They are contagious and can spread through close contact, including kissing. While there's no cure for cold sores, various treatments may help manage symptoms and outbreaks.

What are other causes of blisters on the lips?

Blisters on the lips can form due to various factors. And all of the lesions have a name depending on the cause. 

Here are some common blisters that may form on your lips and are often confused with cold sores.

Canker sores

A canker sore also called an aphthous ulcer, is an open and painful mouth sore or ulcer — the most common type of mouth ulcer. Canker sores are usually yellow or white and surrounded by red, inflamed soft tissue. They do not blister. 

Unlike cold sores, canker lesions aren't contagious and don’t stem from an infectious cause. They form inside the oral cavity rather than on the lip's surface. However, they can be painful and can make talking or eating difficult. 

Sunburn blisters

Sunburn lesions can also cause blisters on the lips and are extremely painful. The blisters form several hours after sun exposure.

The lesions are small, white, and fluid-filled in appearance. Although the pain may subside within 48 hours, the blisters may take a minimum of one week to fade away. 

Sunburn blisters can cause the following if they’re associated with extensive, systemic sunburn or even sun poisoning:

  • Vomiting

  • Dizziness

  • Fevers

  • Nausea 

  • Chills

Angular cheilitis 

This inflammatory condition brings about swollen red patches around the corners of your mouth on the outside of your lips. In addition, the cracked, dry skin becomes susceptible to infection. 

Angular cheilitis may last a few days or become a constant problem depending on its stage. 

Both cold sores and angular cheilitis may cause rawness, redness, or inflammation around the corners of your mouth. However, angular cheilitis only affects the corners of the mouth, while cold sores can form anywhere on the lips and around the mouth. Furthermore, no blisters are expected with angular cheilitis.

Herpetic gingivostomatitis 

Herpetic gingivostomatitis is caused by the same virus that causes cold sores and is the most common presentation of this HSV in young children. This mouth infection brings about blistering sores that occur on the gums and inside the lips. Although the infection is in the mouth area, it may sometimes spread to other parts of your body, like the nose and genitals. 

Folate deficiency

A folate deficiency may lead to canker sores, although the exact mechanism is unknown. If this deficiency, along with possible vitamin B12, also results in anemia, you may experience symptoms like fatigue and weakness.

What are the similarities between cold sores and blisters on the lips?

Cold sores are blisters on the vermilion border caused by the herpes simplex virus. However, cold sores and blisters on the lips share some common characteristics. For instance, they both form on the lips, although cold sores most commonly appear on the vermilion border — the border between the lip and the skin.

In fact, a cold sore can be classified as a blister on the lip. Blisters on the lip is an umbrella term for all lesions formed on or around the lips or mouth.

Moreover, blisters on the skin can be caused by anything, including herpes simplex, the virus that causes cold sores. 

How are cold sores and lip blisters different?

How do you differentiate a cold sore from a lip blister? It's pretty simple. First, consider the location of the lesions. Cold sores form on or around the lips and can be grouped in patches if not singular. Furthermore, blistering is just one stage in the evolution of a cold sore. Lip blisters, however, can form anywhere on or around the mouth — some occur inside the mouth.

Moreover, cold sores are caused by the herpes simplex virus. At the same time, lip blisters can stem from several causes, including sunburn, autoimmune disorders, canker sores, syphilis, various infections, and oral cancer. 

Also, cold sores are highly contagious, whereas some blisters on the lips may not be contagious. 

Treatment options

Cold sores and blisters on the lips may go away on their own without any treatment. But sometimes, you need some treatment and home care to relieve symptoms. 

Cold sore treatment options

There's no cure for cold sores. However, you can manage symptoms in various ways, including using:

  • Medications: oral antivirals like valacyclovir and acyclovir can help treat cold sores. 

  • Creams and ointments: antiviral ointments like penciclovir can help you control pain and promote healing from cold sores. You can also try over-the-counter creams like docosanol to shorten the cold sore outbreak.

  • Home remedies: some home remedies can help ease symptoms of cold sores. For instance, you can apply ice over the cold sores, use lip balm containing lemon extract, and apply aloe vera gel.

Treatment for lip blisters

Treatment for lip blisters varies depending on the type of lesions. However, a mix of medications, creams, ointments, and home remedies might relieve lip blisters.

Always speak to your doctor when your lip blisters don't go away with medications, creams, and home remedies. 

The lowdown

Most people often use lip blisters and cold sores interchangeably. However, blisters on the lips and cold sores have some differences and similarities. Therefore, it's essential to understand the differences in causes, symptoms, and treatments between the two.


Can you have a blister on your lip that isn't a cold sore?

Yes. Not all blisters on the lips are cold sores — some form due to sunburn, cankers, or folate deficiency.

What can be mistaken for a cold sore on the lip?

Many people mistake cold sores for other blisters like gingivostomatitis and sunburn blisters.

Have you considered clinical trials for Cold sores?

We make it easy for you to participate in a clinical trial for Cold sores, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

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