HI - Would Highlands Powder For Muscle Cramps Be Safe For A 90 Year Old Woman On Metropolol For High BP?

HI - Would Highlands Powder for muscle cramps be safe for a 90 year old woman on Metropolol for high blood pressure? Her pressure is at a regulated level right now. She had an ultrasound of her legs last week and there are no blood clots shown. She suffers with severe cramping and her doctor does not seem concerned. So, we d like to try something OTC for her. Thank you for any input.