Sudden onset of slurred speech, any ideas?

Initial signs similar to bells palsy, drooping right eye, puffy right cheek, slurred speech, sudden onset. No further stroke signs. CT scan shows no sign of stroke. Eye and cheek mostly cleared up in the 5 days since onset, but the slurred speech although disappearing returns each time she eats, anything from 30 mins to about 2 hours approximately. Can also get slurred speech if talking for a period and the more she talks the worse it tends to be, clearing up after resting voice for a short time. Dont know if there's a connection but always taken Tramadol and Paracetomol, but was prescribed Methocarbamol and slurring started about 8 days after Methocarbamol began. Was told to stop the Methocarbamol on the day the problems began in case of allergy to it and given antihistamines but its been 5 days since it all began and still no change, slurring still ongoing when talking for any time and always after eating anything. GP and hospitals so far have no ideas. Nothing has changed lately other than the 8 days of Methocarbamol. No falls or anything. She is type 2 diabetic not on insulin, controlled by medication only which she's had for a couple of years.