Hi and thanks for the query.
This is most likely related to your allergies and the because of the dependency.
Sometimes, vitamin deficiency can also result in tongue swelling and GERD is also a factor since, acid trickles up in the night to irritate the throat and oral mucosa including the tongue.
This is definitely not something serious since, those present with persistent swelling, ulceration and pain.
I would suggest that in order to counter this you should have the GERD treated and sleep with a head up tilt.
Have you vitamin B levels checked, this can be done by a blood test. Once, the underlying cause is alleviated. The tongue swelling should subside.
Let me know if you have further questions.
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