Can you take magnesium citrate vitamins while on Accutane?

I am 19 years old, female, 5’3 and weigh 130lbs. i started accutane a month ago and i’m wondering if it’s okay to take magnesium on it. i have hypothyroidism and half my thyroid removed. my endocrine took me off levothyroxine at age 17 and put me on phentermine. after taking phentermine for a year i now have horrible digestive problems. i’ve completely changed my diet to vegan& gluten free but still, magnesium is the ONLY thing that helps me go to bathroom.