Well there is moderate drug interaction between Cheratussin AC and Methylprednisolone.
So it's advised not to use them together.
You can give her Bromfed with methylprednisolone.
You should elevate her head side of bed.
Also give her warm liquids.
Use a humidifier in your room.
And it is good to see her doctor again and further blood work like CBC,ESR,Absolute eosinophil count,Chest X-ray to rule out underlying possible cause.
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