3 doctors weighed in:

A blister in the mouth means I have anything contagious, or not?

3 doctors weighed in
Dr. Daniel Wolter
Dentistry
1 doctor agrees

In brief: Sometimes

There are many conditions which cause blisters in the mouth.
Most of them are not contagious. However, one of the most common causes of blisters is from the herpes virus, which is contagious. So, the only way to know for sure is to see a dentist right away. If the blister heals, it won't be possible to know what it was, since it will be gone. You should have it checked now.

In brief: Sometimes

There are many conditions which cause blisters in the mouth.
Most of them are not contagious. However, one of the most common causes of blisters is from the herpes virus, which is contagious. So, the only way to know for sure is to see a dentist right away. If the blister heals, it won't be possible to know what it was, since it will be gone. You should have it checked now.
Dr. Daniel Wolter
Dr. Daniel Wolter
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In brief: Not necessarily

The blister may come from trauma, a burn, a clogged minor salivary gland or other cause.
One possibility is something viral but it will probably have to be ruled out by your dentist or physician doing a visual examination and evaluation of your history.

In brief: Not necessarily

The blister may come from trauma, a burn, a clogged minor salivary gland or other cause.
One possibility is something viral but it will probably have to be ruled out by your dentist or physician doing a visual examination and evaluation of your history.
Dr. Willis Hardesty
Dr. Willis Hardesty
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Dr. John Ebner
Dermatology

In brief: It's possible

Blisters, erosions and sores in the mouth can be caused by many different things.
Some are contagious (herpes simplex) and many are not (canker sores, lichen planus, pemphigus vulgaris). Have this checked out to find the exact cause as this is important for long term treatment decisions.

In brief: It's possible

Blisters, erosions and sores in the mouth can be caused by many different things.
Some are contagious (herpes simplex) and many are not (canker sores, lichen planus, pemphigus vulgaris). Have this checked out to find the exact cause as this is important for long term treatment decisions.
Dr. John Ebner
Dr. John Ebner
Thank
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