Blisters in the mouth are sores which may appear on soft tissues such as the gums, lips, tongue and the inside of the cheeks. They are quite common and usually disappear within a week or two.
However, these sores can make it uncomfortable when eating and drinking, and sometimes when swallowing.
While most mouth sores do not carry any long-term harm to your health, more severe or recurring types of sores may need medical attention. Sores are usually different in color to the surrounding tissues. Depending on the type of sore and its cause, this color could be white, red, yellow or purple.
Blister in Mouth: What Are the Main Causes?
Mouth blisters can be caused by a variety of reasons. Some of these are down to lifestyles and bad habits, while others could be down to underlying health issues and exposure to certain viruses. The following are some of the more common causes of a mouth blister.
Stress
Aggressive brushing using a hard-bristled toothbrush
Biting the inside of your mouth
Tobacco
Burning the mouth when eating
Hormones
Orthodontic devices such as braces that irritate the soft tissues in the mouth
The health issues and viruses which increase your risk from sores include:
Crohn’s disease
Anemia
HIV and Aids
Human Papilloma Virus
Herpes Simplex Virus
Mononucleosis
Irritable bowel syndrome
These are some of the contributing risk factors for developing blisters in the mouth. Different types of sores can have different causes and therefore it is useful to consider the main types of mouth blisters.
Common Types of Mouth Blisters
Canker Sores
This common form of blistering can affect up to 20% of people. Although they can be painful, they are harmless and should disappear within a week or two. Canker sores tend to be red and can have white, gray or yellow areas within them.
This form of sore is not contagious and may result from biting the inside of your mouth or gums. A weakened immune system can also increase your risk from canker sores, as can stress, Crohn’s disease and irritable bowel syndrome.
Cold Sores
This is another common type of mouth blister that can affect up to 40% of people. Often red in color, they are normally located near the mouth and on the lips. Unlike canker sores, cold sores are contagious and can be transmitted through kissing and sharing food and utensils.
Cold sores are caused by the herpes simplex virus. Stress and a weakened immune system can contribute to cold sores, as can overexposure to the sun. A tingling or burning sensation may forewarn you of cold sores. These blisters can last for up to six weeks.
Oral Thrush
Symptoms of oral thrush include creamy white blisters on the tongue or soft tissues in the mouth which could be scraped off. Oral thrush is caused by excess candida, a naturally occurring yeast within the body. It does not look too pretty when sticking your tongue out but can usually be cleared within a week or two using anti-fungal medication.
Oral thrush does not tend to be contagious, although it is best to be careful if you have such blistering. Someone with thrush can experience pain when eating, and they may also struggle to taste their food.
Gingivostomatitis
This form of sore is most likely to be seen in children. It can seem similar to canker sores, and forms on the gums or on the inside of the cheeks. The sores can be caused by a bacterial or viral infection, and can often be the result of poor oral hygiene. They can last up to three weeks.
Leukoplakia
This form of mouth blister involves white patches develop on the soft tissues. It is mostly associated with smoking and those who use tobacco products.
Generally, this type of sore is harmless and will clear up of its own accord. However, in some instances it can increase the risk of developing oral cancer.
Oral Cancer
Ulcers or red and white sores in the mouth or on the lips which do not heal or go away can be a sign of oral cancer. Your dentist can check for oral cancer and perform a biopsy to check for cancerous cells. Early detection of cancer helps with treatment and increases the chance of a more successful outcome.
Treating Mouth Sores
Mouth sores usually clear within a couple of weeks. To relieve any pain when you have mouth sores you should avoid hot and spicy foods, as well as tobacco and alcohol. Cold foods such as ice pops may help soothe the area around the blistering.
Additionally, you can gargle with warm saltwater a few times throughout the day. Over-the-counter pain relief can also be useful in combating any discomfort caused by a mouth blister. One thing you should avoid is the temptation to squeeze or pick at a sore.
While most mouth sores will not require a medical diagnosis, if they persist or are severe then you should consult a doctor. You might be prescribed medication to treat any blistering caused by an infection. A doctor may also prescribe pain relief, anti-inflammatory medication or a steroid gel.
Prevention
While prevention is better than cure, mouth sores are hard to prevent completely. However, some tips to help avoid them include:
Good oral hygiene, including regular dental appointments
Use a soft-bristled toothbrush
A balanced, nutritious diet
Stay hydrated
Avoid hot, spicy foods
Avoid tobacco and limit alcohol
Practice ways to reduce stress, such as meditation
Protect the lips with lip balm from exposure to the sun
Chew slowly
Do not bite or chew the inside of the mouth
Mouth blisters or sores are pretty common. While they can be uncomfortable, most clear up within a week or two. However, if they persist, recur or present more severe symptoms you should consult with your doctor, as it could be a sign of a more serious condition.
When it comes to a friendly, caring, and professional dentist in Cheadle Hulme, you won’t find better than Cheadle Hulme Dental and Cosmetics. Why not book an appointment by contacting us directly at 0161 486 0743? We look forward to welcoming you.
I came across this dental practice when doing research on having braces. Initially I had a consultation regarding options. The practice is lovely and clean. The staff are amazing, they are very attentive. I am glad I chose here to have my treatment. I’m now roughly 7/8 appointments in, all of my visits have been great. I would highly recommend. If you are looking for dental or orthodontist - these guys are really good at what they do!
Reception area lovely and staff very welcoming. I was impressed by the attention to detail with the photos of my teeth/gums so when I got to see Hope she had them on screen. Hope was very knowledgable and explained everything from options to finance. Very impressed with my first visit. If I could I would have had the treatment right then and there as the whole experience was very relaxed but professional. Highly recommend.
I booked a visit as I was looking for a second opinion on tooth implant. It is my top front tooth so definitely want to get it right.Staff have been very friendly, inviting and professional. After seeing modern equipment used plus the customer service I have decided to go ahead with Cheadle Hulme dental clinic.
Had a lovely experience at Cheadle Hulme Dental .I was referred her by my own Dentist for a scan on my wisdom tooth. The practice is very clean and inviting when you walk in the staff on the desk are welcome too. There were refreshments available for customers hot drinks and water which I thought was nice you don’t normally see that at a dental practice. Wasn’t waiting to long to be seen. when called for my scan everything was explained to me . Would definitely recommend Cheadle Hulme Dental and Cosmetic.
I can’t recommend Cheadle Hulme Dental highly enough!Back in October 2025, I had composite bonding on my upper front teeth after breaking my two front teeth. From my very first appointment, Hope made me feel completely at ease. She was incredibly welcoming, explained every step of the process in detail, was transparent about the pricing, and made sure I knew they offered interest-free payment plans, which was a huge help.Unfortunately, around six months later I chipped one of the bonded teeth while eating. I contacted the practice, and Megan was fantastic. She arranged an appointment for me quickly and made the whole process stress-free.At my appointment, Mo repaired my teeth, and I honestly couldn’t be happier. His work is exceptional, and he was professional, reassuring, and sorted everything out without any hassle.The whole team genuinely cares about their patients and always goes above and beyond to provide outstanding care. I wouldn’t hesitate to return for any future dental treatment and would highly recommend Cheadle Hulme Dental to anyone looking for a friendly, professional, and caring practice.Thank you to the whole team for looking after me so well!
I originally went with an emergency ( having not been to the Dentist for many many years, due to a phobia) I saw Ben who was fantastic and really put me at ease, he was extremely patient with me and talked me through some ways they can support patients who have a fear of going.I’ve since been back to register with them as a new patient and had a full check up due to how supportive they were.The surgery itself is extremely tidy and clean and all staff I have come across were friendly and professional.
I had a very positive experience at Cheadle Hulme Dental & Aesthetics. Ben was extremely professional, knowledgeable, and caring. He managed to save and repair my child's tooth when other dentists had recommended extraction, which we were very grateful for.The entire team was friendly, welcoming, and helpful throughout our visits. The practice was clean, modern, and well-maintained, and we felt genuinely cared for as patients from start to finish.The cost of treatment was also very reasonable and represented excellent value for the quality of care provided.I would highly recommend Ben and the whole team at Cheadle Hulme Dental & Aesthetics to anyone looking for high-quality dental care.
I think we can all agree that going to the dentist can be nerve wracking, but the team at Cheadle Hulme Dental made me feel really welcome from the moment i arrived, especially as I had my son with me.The ladies on reception were lovely, and Hope was so reassuring and helpful in explaining everything that was needed. There was absolutely no pressure whatsoever, which made the whole experience much more comfortable.The practice was really clean and they even offered tea, coffee, biscuits, and water which was such a nice touch. I’d definitely recommend them to anyone who feels nervous about visiting the dentist.
An amazing dental practice that I have been a customer of for nearly 15 years. The dental practice is lovely and super modern. The reception team are always very friendly. Our dentist Mo is very professional, putting my daughter and I at ease. I look forward to visiting again and recommend this practice to all. Thank you team!
I originally went with an emergency ( having not been to the Dentist for many many years, due to a phobia) I saw Ben who was fantastic and really put me at ease, he was extremely patient with me and talked me through some ways they can support patients who have a fear of going.I’ve since been back to register with them as a new patient and had a full check up due to how supportive they were.The surgery itself is extremely tidy and clean and all staff I have come across were friendly and professional.