Are allergy, infection, or thrush, causes of an inflamed throat?

Yes they all can: Allergies can cause drainage that goes down the back of your throat, causing irritation rarely is it painful. Usu results in throat clearing and phlegm. Bacterial and viral infections can cause throat to be red and painful. Thrush, rare in adults unless on certain meds or immunosuppressed usu causes un-washable white coating on tongue, cheeks, and can affect the throat. A doc can help tell.