Brief Answer:
It may be due to allergietic reaction.

Detailed Answer:
Hello,
I have gone through your query and here is my advice.

It may be due to allergietic reaction.

Let me know if you have any other symptoms like runny nose, fever, itchy eyes, hives, difficulty in breathing, history of eating any new or allergietic foods, insect bite, change of soap, perfume or any other cosmetics.

As per your history you can take tab Allegra 12O mg every 12 hourly, can apply ointment hydrocortisone locally after dermatologist consultation.

For further evaluation, you may require blood investigations, complete blood count, blood culture, random blood sugar after detailed medical examination and dermatologist consultation.

Till then you can apply lactocalamine lotion locally, keep your self hydrated and maintain proper hygiene, avoid allergens.

Hope I have answered your query, let me know if I can assist you further.
Thank you.

Regards,
Dr Shyam Kale.

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