Brief Answer:
Yeast infection

Detailed Answer:
Hello

Thanks for the query

Long term antibiotic therapy is known to cause fungal infections, however this is seen more often in patients in an immunocompromised state like diabetes, transplant patients or patients on steroids.
If you notice white patches over your throat, tongue or oral mucosa then it is most likely a yeast infection. If it is just red then probably it is just an inflammation.

Here are my suggestions
1. Gargle your throat with warm salted water three times day
2. Avoid cold food and beverages
3. Avoid spicy food
4. Drink warm water
5. Tab levocetrizine once at night can reduce the burning

I hope I was of help, if you have any further queries please get back to me

Regards

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