Absolutely! Meds can cause BP to fall too low and cause weakness, dizziness, fatigue, sweating, lightheadedness, shaking, nausea, etc...and fainting. She definitely needs her BP meds evaluated.
What concerns me, though, is the smile or drooped mouth. Those are signs of a seizure. As one mom said, blood sugar could be a concern, too.
She absolutely needs to be check out by the doc. One easy thing to do is buy a BP monitor so she can check her BP when she feels symptomatic. Have her take it to the doc with her on her next checkup to test it against theirs and make sure it's accurate. Also, ask for a Hemoglobin A1C and a Fasting Blood Sugar test. (It's likely they will order it anyway) and have them test her sugar with a fingerstick there in the office. In our office we have monitors that are supplied by the drug companies at no cost to patients. Perhaps she could ask for one just to have on hand so next time it happens her BS can be checked right away.
That's all I can think of right off hand...stress to her the importance of nutrition...I hope you find some answers.
Keep us posted!