You are eating breakfast but suddenly your teeth bite into the inner side of your cheek. An injury to the tissues has been incurred and that results in a blood blister.

It is a sac sometimes filled with blood or another fluid in the oral cavity.

They are dark red or purplish in color and will burst on their own, so will it heal quickly.

This raised area of the skin is sometimes painful, however, symptoms are usually mild.

This article discusses what causes these blisters in the mouth and how you can manage them.

Keep reading to know more about healing these uncomfortable sores.

blood blister in mouth

Blood Blister in Mouth: Causes

A blister can appear due to several reasons. Some of these are totally harmless.

They also occur spontaneously without any certain cause.

Harmless Causes Behind the blisters 

  • eating hot, hard or crunchy food
  • stress
  • accidentally biting the inside of the cheek
  • teeth braces irritating the mouth
  • dentures not fitting properly
  • angina bullosa hemorrhagica
  • local anesthetic injection
  • inhaling steroid drugs
  • dental procedure such as impressions or crowns

Oral blisters forming as a result of angina bullosa hemorrhagic occur spontaneously and rupture in a few minutes.

It is a rare disorder that is harmless unless a big blister blocks the airways.

However, unlike blood blister, they do not have any systemic disorder causing them.

Besides these rather harmless reasons, there are some serious causes behind these oral raised blisters too.

dental work irritating mouth

Serious Causes

  • oral herpes
  • renal failure
  • trauma
  • oral cancer
  • allergies
  • diabetes
  • alcohol abuse
  • vitamin deficiencies
  • low platelet count
  • chemotherapy and radiation

Conditions like oral cancer, herpes, diabetes and renal failure can form these blisters.

They are one of the symptoms pointing towards a greater health concern.

Though, other than that, allergies to certain foods can also irritate the lining of your mouth.

Acidic foods and cinnamon flavoring or astringents in toothpaste and mouthwash can usually result in an allergic reaction.

The common cause is usually trauma to the mouth in the form of biting or scalding the lip or inner cheek.

Similarly, it can occur because of burning the mouth with hot food and puncturing the mouth with rather sharp and crunchy food.

In this case, the blister forms pretty quickly after the incident.

Thrombocytopenia is a condition whereby your platelets reduce.

This can be due to medications, the immune system destroying platelets and also pregnancy.

One of its symptoms is the presence of blisters in the mouth.

blood blister symptoms


There may not be any significant symptom besides having the blister itself.

However, the feeling of having one in your mouth is certainly uncomfortable.

There can be slight burning and pain on the spot sometimes, however, some do not pain at all.

These go away when the blister ruptures.

You will usually find them on soft surfaces such as the tongue, underside of the lips, or cheek.

Though there may not be only one at a time, several can occur together too.

The color will be dark red or purple and in between.

They can contain blood or some other fluid hence forming a fluid-filled sac.

Since they are big enough for you to feel and even sometimes see them, the blisters will be uncomfortable.

While they are typically painful, the pain subsides when they pop on their own.

In the meanwhile, their presence makes chewing food and brushing teeth difficult.

If there is an underlying serious cause behind these, that could result in other symptoms as well.

So when should you know if it is time to consult your doctor? 

Usually, the blisters will rupture on their own and you will not require special medical attention.

However, some signs can be the cause of concern pointing towards serious underlying conditions that need medical attention.

For instance, if the blisters do not heal or keep recurring, check with your doctor to get proper treatment.

Other than that, if they are very large, hinder your eating and drinking and form on the lips, a medical checkup can ease the discomfort they cause.

If you were dentures and braces, blisters can interfere with the fitting.

Hence, go to your dentist if they are interrupting the braces and dentures from fitting in your mouth fully.

Otherwise, you can also try some remedies.

treatment remedies

Blood Blister in Mouth Home Remedy

Usually, the blisters heal on their own at their own time.

In the meanwhile, you can manage the symptoms in order to reduce the pain and discomfort using these remedies.


Surprised! Aren’t you?

It shouldn’t really be surprising because cucumber contains silica.

This chemical helps in healing and skin regeneration.

Hence, it will heal your blister faster.

To use it, cut a small, thin slice of cold cucumber and hold it in place of the blister.

Use it several times a day.

You can also drink cucumber water to aid in healing.


Turmeric reduces inflammation and pain.

Curcumin in turmeric treats skin disorders and also inflammation.

Mix a teaspoon of honey with turmeric powder and apply the paste to the blister to heal it.


If you apply ice to the injury inside the mouth immediately then it prevents the formation of the blister.

It can also relieve the inflammation and heal it.

Directly hold an ice cube on the affected area.

Do so for 10 minutes many times a day.

Plus, apply light pressure to contain the bleeding.

A frozen popsicle can also help in this regard.


Chamomile tea can help with mouth sores and blisters.

This is due to its soothing properties that provide relief.

Hence, a person with blisters can drink chamomile tea in order to relieve soreness and heal.

Witch Hazel 

Witch Hazel contains astringent tannins.

They not only reduce pain and inflammation but also dry the blisters.

To use it simply dab a cotton ball in witch hazel and apply it to the affected area.

Keep your mouth open so that the witch hazel dries up.

Repeat it throughout the day.

Besides that, you can also implement some tips and practice the prevention of irritants to give the blister time to heal.

treating a sore

Treatment and Tips

If you are suffering from pain, you can simply apply ice packs or take over-the-counter pain relievers to feel better.

Let the blister heal and rupture on its own.

Do not try to pop it.

This can increase the chances of getting an infection.

While you are healing the blister, you should also refrain from certain irritants that will prevent them from recurring.

These include hot, salty and spicy food.

During the time the blister heals, eat only soft foods.

A soft food diet can prevent it from worsening and is easier to eat while you are having difficulty chewing food.

If you think your dentures or braces are causing it, talk to your dentist so that they can fix it.

If necessary, remove your dentures till the sore heals.

Do not wear them because irritating the sore can make it last longer.

While practicing these tips, your blister should heal soon.

These are usually benign that take a week or two to heal properly.

However, if it does not heal in that time, it is better to visit your doctor.

Also, other conditions such as a big blister interfering with your breathing and swallowing, an extremely painful one that hinders daily functioning and a recurrent one are cause for concern.

Also if you see notice some signs of infection such as pus leaking out, red tissue around it and the affected area becoming warm then it is concerning.

Your doctor may prescribe medicines to treat the infection, a soothing mouthwash to speed up the process of healing.

Other than that they can recommend pain medications so that it relieves pain.

Hence, being mindful of what you eat, drink and practice can keep them at bay.

tips for sore

Blood Blister vs Mouth Sores

Now that you know how to treat and deal with blood blister, do you think they are the same as mouth sores?

Mouth sores like canker sores and fever blisters also occur in the mouth like blood blisters.

They are all red in color, however, all of these are different.

A fever blister begins with a tingling sensation in the area the blister forms.

Accompanying that, would be a fever and swollen lymph nodes.

The most common areas where they form is not in the mouth rather under the nose or on the lips.

On the other hand, canker sores begin as red ulcers and they have a white or yellow film covering them.

Whereas blood blisters are usually red or purple in color without any covering.

They also occur spontaneously without any tingling sensation.

So they appear suddenly and heal on their own too.

Usually, they do not cause any fever alongside, unless it points towards an underlying condition or infection.

Moreover, it certainly forms inside the mouth, not under the nose.


Blood blisters are different from fever blisters or canker sores.

However, they are a benign condition that isn’t harmful unless it is a symptom of another condition.

Therefore, consult your doctor if you have other symptoms besides minimal pain and irritation.