Brief Answer:
Herpes Simplex virus is common cause

Detailed Answer:
Hi,

Blisters on lips are most commonly caused by Herpes Simplex virus which is normally present in almost everyone and gets reactivated whenever a person's immunity is low.

This infection typically presents with tingling and itching on lips and later formation of group of fluid filled blisters usually on lips and inner mouth.

Dry lips may predispose to have these blisters.

Triggers for herpes infection include:
1.Exposure to extreme cold or sunlight
2.Any illness with fever
3.Increased stress levels.

I am suspecting herpes virus infection in your case based on the description given in your query.
I suggest application of acyclovir cream over the blister three to four times a day.
Do not scratch as this might cause spread of the blisters.
They will heal without scarring within 5-7 days.
The other reasons causing dry lips include vitamin B deficiency and yeast infection of lips.
I hope I have cleared your doubts.
Thanks.

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Brief Answer:
Reactivation occurs whenever your immunity is low

Detailed Answer:
Hi,

As I have mentioned in my previous answer, herpes virus has a very unique property of lying dormant (hidden) in our body and gets reactivated whenever the persons immunity gets low.

Repeated activations can occur if the person has increased stress levels, has been on medications which cause immune suppression or suffering from prolonged illness.

I suggest Tab Atarax twice daily for two days for the itching. Please get it prescribed by your doctor.

If it does not reduce, I suggest you get the lips examined again to rule out other causes.

Thanks.

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