Oh My! I'm sorry I didn't see your post earlier.
I'll cut right to the chase - did you take your partner for medical care? How is she doing now.
I won't go into details till I hear back from you. Her reaction is not normal to a change - or addition in meds. Her MD or an MD should be consulted asap.
I'll wait to hear from you.
No, that is not normal. However, that does not mean you *must* start worrying about it this second. Nonetheless, it *does mean* you need to take your partner in, ASAP, to discuss this with her doctor.
This sudden problem with speech can be VERY serious (e.g. impending stroke, etc.), or, it could be something as simple as the body/mind getting used to a new "medicine combination."
So right away, at LEAST call your doctor's office -- and if they say something like "we can get you in a week from now," tell the nurse or whoever to "please relay this information to the doctor now" so if the doctor decides it's serious he/she will call you and bump your appointment sooner.
After you do that, you can spend some time on the computer googling this symptom and the meds, just to see if others have the same issue.