Lip blisters are very common but are typically minor. While aggressive allergic reactions and undetected diseases can pose a more serious threat, most blisters are the by-product of injury, trauma, or exposure to different triggers.

Environmental changes, hot beverages, and lip biting can all lead to blisters. Due to the general sensitivity of lips, it is easy to cause abrasion, redness, and inflammation.

Blisters that fail to heal can be a problem. It’s not uncommon for them to assist with the identification of underlying health issues that have yet to be diagnosed. Chronic blisters that are accompanied by lip swelling should be checked by a medical practitioner.

Let’s explore the topic of lip blisters and determine the ‘potential’ causes.

Why Do We Get Small Blisters on the Lips?

Small lip blisters can be due to a host of internal and external factors. These range from minor abrasions caused by trauma through to blisters brought on by a specific illness. Even something as ‘seemingly’ harmless as a single ingredient in a product can cause a blister to form on the inside or outside of the lip.

What sets our lips apart from other areas of skin is the exposure and sensitivity. Always in use, our lips see a significant amount of activity. Exposed to many types of environments, our lips are often the guinea pig for our behaviors. When you factor in the general sensitivity, it becomes easier to understand how they could become damaged in some way.

While blistered lips could be a sign of something more serious, most of the time this is not the case. Blistering and cracking are common. In most cases, the blisters will clear up without treatment.

However, it is sensible to monitor the site of the blister for any significant changes (redness, oozing, pain, increases in size, spreading, etc.) Also, a lack of healing could be a sign of a more concerning issue that requires attention from your medical practitioner.

Cold Sores

Cold sores can be identified through sensation and a well-defined visual.

Developing on your lips, cold sores begin with a tingle or burning at the formation site. This is called the prodromal stage.

Within 24-48 hours after your original symptoms, a cluster of blisters will begin to form. They are filled with fluid, and this can cause pain. The skin in and around the site will typically turn red.

Just days after the initial blistering, the cluster itself will burst. Regarded as the most painful stage of the cold sore life cycle, each blister will drain. The appearance of fluid is a by-product of the drainage. Small traces of blood, while uncommon, can also appear.

Once the blister has been replaced by an ulcer, a scab will slowly begin to form. Not long after, if healing has not been compromised, the scab will naturally flake away. This process will reveal new skin underneath the surface.

Cold sore facts:

  • Fever blisters are born from the herpes simplex virus (HSV-1). The blisters that form are a by-product of the herpes virus being triggered or awakened.
  • Cold sores follow a distinct life cycle.[1] If you have a blister that suddenly appears then vanishes within 24 hours, it is NOT a cold sore.
  • Fever blisters form in clusters and contain clear fluid. Pay attention to this essential visual. It will help you to identify the medical problem better.
  • Cold sores begin as a sensation, not a blister. A tingling (or burning) at a specific location on the lip are the first symptoms of cold sore development.

Blood Blisters

These are raised blisters that are filled with blood. They are primarily the by-product of blood vessels bursting just below the surface of the skin. If the leaked blood becomes trapped under the skin, a blister is likely to form.

Although the cause is mostly unknown, here are some of the primary reasons:

  • Stress
  • Allergic reaction
  • Dental work (braces, dentures, etc.)
  • Angina bullosa hemorrhagica[2] – This is a relatively rare condition that causes blood blisters to form spontaneously, usually due to local trauma or chronic use of inhaled steroids.
  • Lip biting

Although blood blisters usually heal naturally, some situations need to be carefully monitored. Blisters that show little sign of healing and frequently recurring blisters should be checked by a medical professional.

Other issues include:

  • Large blood blisters
  • Blisters that hinder eating and drinking
  • Blisters that cover the lips causing intense swelling
  • Perpetual blisters caused by ill-fitting braces or dentures

Cancer Blisters

Unfortunately, a lip blister can sometimes be a sign of cancer.

The National Institute of Dental and Craniofacial Research have stated that the majority of oral cancers are linked to tobacco and alcohol use. If you drink or smoke regularly, you should monitor the situation far more closely.

Intense exposure to the sun is also a major risk factor in the development of lip cancer. If your livelihood involves long hours in the sun or you spend a lot of time outdoors in sunny weather, it is critical to take extra precautions.

Common signs of lip cancer include, but are not limited to:

  • Any blister, ulcer, lesion or lump that does NOT go away
  • Red and/or white patches on the lip
  • Intense pain and/or bleeding of the lip
  • Swelling of the jaw

Many forms of lip cancers do not produce red flag and obvious symptoms. In fact, many issues are often not noticed until a routine dental examination is performed.

If you are experiencing any of these symptoms, regardless of the degree, you MUST consult your primary care physician. Drinking, tobacco use, and heavy sun exposure increase your risk.

Sun Blisters

Lip blisters due to the sun are common, hence the reason that they’re often referred to as ‘sun blisters.’ Young people and those who work outdoors are most vulnerable. Sun exposure can burn your lip region if it is not adequately protected.

Although lip blistering can be painful and cause sleeplessness, usually it is not severe. However, long-term (or excessive) exposure to the sun should be avoided. As discussed earlier, it has the potential to lead to a cancerous growth.

Always apply a lip balm that blocks out UV rays before spending any time in direct sunlight.

Sources of pain relief include:

  • Ice/cold compress
  • Ibuprofen
  • Aloe Vera gel
  • Antibiotic ointment

Never burst your blisters as it can lead to infection, delay healing, and cause intense pain. Instead, soothe your discomfort (see above) and allow them to heal on their own.

Water Blisters

Water blisters, also known as mucous cysts and mucocele, are fluid-filled blisters that primarily develop on the lower lip. They are often red or bluish and contain a clear liquid.

It is theorized that mucous cysts are caused by the intentional or accidental sucking of lip tissue between your teeth. However, it is possible for water blisters to form without any direct cause. While they only last for a short time and are painless, some can become permanent if they do not burst.

If your water blister does not burst naturally, it may require removal by your dentist.

Can you get blisters from chapped lips?

Burnt Lips

A burnt lip is the result of an extreme temperature being directly applied to your lip. This is usually caused by hot food or beverages, such as drinking black coffee.

Treatment would be similar to that of a sunburned lip. Ice/cold compress, Ibuprofen, or aloe vera gel would be among the safest treatment recommendations.

Although blistering that’s caused by a burn can result in scarring, this is rare. If treatment is applied within a few moments of the incident, the odds of full healing increase dramatically.

Canker Sores

Defined as small and shallow ulcers, canker sores appear inside the mouth.[4] They DON’T form on the lip itself. These sores are known to make eating and talking quite uncomfortable.

Very common, canker sores can appear an average of 3-4 times per year and last for up to one week. While all ages and genders can potentially be affected, canker sores primarily occur when you’re aged between 10 and 20.

While the precise cause is unknown, certain foods and high levels of stress are known risk factors. Considering they can be caused by some chronic illnesses, make sure you check with your doctor if you they appear often. Cold sores and canker sores are not the same thing and have nothing directly in common. Cold sores are the by-product of herpes simplex one, virus which is an extremely contagious virus.

Allergic Reactions

Lip swelling is a common symptom of an allergic reaction. From certain foods to medications, a swollen and blistered lip is often an unpleasant side effect. As a way to protect itself from intrusion, your immune system will invoke swelling as a means of defense.

While most allergic reactions are brief, and the symptoms aren’t that severe, they can sometimes be life-threatening. For example, a condition called anaphylaxis[5] requires immediate medical attention. Symptoms include severe lip and mouth swelling, itchy eyes and face, and difficulty breathing.

Chapped Lips

While chapping can irritate current blisters on the lips, the likelihood of chapping causing a blister is extremely low. Blistered lips are typically the result of a virus, trauma (injury), heat exposure, an allergy, or a burn. Of course, chapped lips CAN cause cold sores on the lips.

Are you concerned about chapping leading to additional problems? Well, you should soothe your lips with a healing lip balm. This will help to shield you from harsh environmental conditions and assist with recovery.

Dental Works

Dental work can cause oral trauma to the mouth and lip area. With a host of tools entering your mouth during treatment, it’s commonplace for cracks and abrasions to occur.

Having extensive dental work can also awaken current mouth sores. Tell your dentist about any existing mouth and/or lip concerns before your procedure – preferably when you book an appointment.

Apply medicated lip balm before and after your visit. While dental tools can harm your lips, the main issue is lip and mouth dryness. Keeping your lips moist is beneficial to the health of your lips.

  • Note: Ill-fitting braces or dentures can also result in blisters. Sharp wiring from braces can irritate your mouth and introduce oral health issues, such as canker sores, lip blisters, gum erosion, infection, and bleeding.

How Do You Get Rid of a Blister on Your Lip?

You need to know what it is and what caused the blister to appear on your lip.

  • Physical trauma or burn: the best treatment is a soothing ointment and anti-inflammatory. Options include ice, a cold compress or medication, such as Ibuprofen.
  • Allergic reaction: your first course of action is to identify and remove the allergen from your life. Once removed, you can treat any swelling that might have occurred.

blister on lip not cold sore

Are Lip Blisters Contagious?

Unless your blister is caused by a bacterial or viral infection, it’s NOT contagious to others. Most blisters are caused by an allergic reaction, hot/cold weather or blunt trauma, so the likelihood of a blister posing a health threat to others is relatively small. But there are exceptions to the rule.

What may seem like a ‘blister on the lip that’s not a cold sore’ could actually be a cold sore. They can be the result of undetected diseases and disorders such as Crohn’s disease[6], Behçet’s syndrome[7], and lupus[8]. If the formation of a blister is accompanied by general sickness symptoms, you should always consult a physician.

Recurrent blisters that give the appearance of a small pimple should be tested for methicillin-resistant Staphylococcus aureus (MRSA) as soon as possible. Rather serious, MRSA is a contagious bacterium that can be contracted through sharing items with an infected individual or having direct contact with the infected person.

The use of public door handles, tables, hand railing, etc. can lead to infection. Very aggressive and resistant to many antibiotics, it is important to get a pus culture done as soon as possible, so proper diagnosis and treatment can begin.

Are Lip Blisters Always Painful?

The pain largely depends on the cause. Cuts, abrasions, pimples, water blisters, allergic reactions, and cold sores all have different levels of discomfort.

Viral blisters have symptoms similar to a cold or flu. Blisters caused by HSV-1 and an allergic reaction are often the most painful ones.

  • Important: When a blister is painful, you should avoid irritants. Note that pain, or an absence of pain, doesn’t always determine the severity. Dangerous lip conditions, such as oral cancer, may only cause minor pain during the early stages.

If you begin to notice that your blister is spreading, becoming larger or won’t go away, you should consult your physician. Don’t keep waiting for the problem to go away on its own.


  1. Everett R.D. (2014) HSV-1 Biology and Life Cycle. In: Diefenbach R., Fraefel C. (eds) Herpes Simplex Virus. Methods in Molecular Biology (Methods and Protocols), vol 1144. Humana Press, New York, NY
  2. Dias KB, Flores AP, Oliveira MG, Carrard VC, Hildebrand LC, Sant’Ana Filho M. Angina bullosa hemorrhagica: report of 7 cases and analysis of 199 cases from the literature. Gen Dent. 2017 May-Jun;65(3):31-36.
  3. More CB, Bhavsar K, Varma S, Tailor M. Oral mucocele: A clinical and histopathological study. Journal of Oral and Maxillofacial Pathology : JOMFP. 2014;18(Suppl 1):S72-S77. doi:10.4103/0973-029X.141370.
  4. Plewa MC, Chatterjee K. Aphthous Stomatitis. [Updated 2017 Oct 6]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2018 Jan-. Available from:
  5. Yue D, Ciccolini A, Avilla E, Waserman S. Food allergy and anaphylaxis. Journal of Asthma and Allergy. 2018;11:111-120. doi:10.2147/JAA.S162456.
  6. Muhvić-Urek M, Tomac-Stojmenović M, Mijandrušić-Sinčić B. Oral pathology in inflammatory bowel disease. World Journal of Gastroenterology. 2016;22(25):5655-5667. doi:10.3748/wjg.v22.i25.5655.
  7. Seoudi N, Bergmeier LA, Drobniewski F, Paster B, Fortune F. The oral mucosal and salivary microbial community of Behçet’s syndrome and recurrent aphthous stomatitis. Journal of Oral Microbiology. 2015;7:10.3402/jom.v7.27150. doi:10.3402/jom.v7.27150.
  8. Chiewchengchol D, Murphy R, Edwards SW, Beresford MW. Mucocutaneous manifestations in juvenile-onset systemic lupus erythematosus: a review of literature. Pediatric Rheumatology Online Journal. 2015;13:1. doi:10.1186/1546-0096-13-1.