Hello,
Thanks for posting your query.
I assume this is the first time you have noticed an oral blood blister and you have no other associated symptoms or any bleeding disorder.
An oral ulcer is the most common cause of a blood blister in mouth. Oral herpes, unknowingly biting the cheek, nutritional deficiency and food allergies too can bring about mouth blisters.However any single blood blister which is self resolving within a week and not recurrent is more likely to be due to benign causes like ulcers or minor trauma to small blood vessels rather than infection ( herpes or other viral) or other significant causes .So in your case it doesn't seem much worrisome & is most likely to be a benign ulcer or trauma which should resolve on its own in a week.
Whatever may be the cause of blood blisters, the habit of smoking can aggravate the condition and prolong healing so it should be avoided.
If there are multiple blisters forming or recurrence of blisters then it would be advisable to get yourself examined by your doctor for confirmation of diagnosis .
Meanwhile please remember that piercing or popping the blister can bring an unbearable amount of pain and further aggravate the problem. Allow the blister to heal naturally to get rid of them at the earliest
Application of topical corticosteroids (fluocinonide gel) and antibiotic mouth washes are also extremely useful to relieve the inflammation associated with this painful condition of the mouth. Also, maintaining oral hygiene is equally important to keep mouth problems at bay.
Hope I have answered your query.
I'll be available for any follow up queries.
In case you have no further queries kindly accept my answer.
Wishing you a speedy recovery.
Regards

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