Woke up with swollen tongue, covered with sores ... and WHITE. That was what happened to me 3 months ago. It hasn't gone away. It still swells and unswells and is white and gets sores around the edges.
It's not geographic tongue. At least mine isn't. It isn't yeast. 4 tests and a tongue biopsy say it isn't.
It's a freak'n mystery. 3 months later. If YOU get a good diagnosis please let me know. Every last stink'n doctor here says 'duh .. I dunno'' or gives me the wrong diagnosis. Two kept saying GERD .. but with me that wasn't possible, I don't have any of the symptoms for it.
In your case it could be an allergic reaction to a drug. At the time mine started, I wasn't on anything to get a reaction to AND it's lasted 3 months. A reaction would have been over by now.