it is risky. i took 2 tiny pebbles of Epsom Salt on an empty stomach. after 6 months got terrifying panic attacks. stopped after i stopped taking it. still, 7 years later i don't feel anything when i drink beer, no longer get runners high when exercising, and barely feel anything during sex.
better off taking magnesium in the form of seeds like hemp seeds or pumpkin seeds soaked overnight. ..sit ups will crush gallblader stones i read.