Any other medical problems or medications?
How long has this been going on?Do you have a sore throat or fever?
Thanks for the additional information.
Well, there are a number of reasons to have whitish coating on the tongue:
2. Leukoplakia (appears as white patches)
3. Lichen planus (white lacy lines)
4. Strep throat
The most likely cause for you would be dehydration becuase of your recent illness. Just keep well hydrated, eat well and this should resolve. If you develop a sore throat or pain, see your regular doctor- you may need antibiotics for strep throat.