If you want oral magnesium to work, you need a form of chelated magnesium.

If blood vessels are constricted in the periphery, then the magnesium can't get there from oral intake. Inflammation will do this.

So using a topical form, may bypass this issue.
I apply the magnesium lotion to my swelling left foot when it gets intense. This takes it down for about 3 days.
I don't think the mag in my blood is getting to that foot which was damaged when I had surgery on it 50 yrs ago. That is my impression watching it swell up for no reason, and go back down when I put the lotion on it. I also apply the mag lotion nightly to my arms for the rest of my body to use.

Epsom-It and Kirkman's cream remain available for sale online topically.