I Am Currently Taking 360 Mg Daily Of Magnesium Citrate/malate,

I am currently taking 360 mg daily of magnesium citrate/malate, after discovering that the mag oxide was only 4% bioavailable (I also take 250 of calcium or try to monitor my diet to ensure I'm getting my daily calcium requirement in). I'm a 52 year old female. My problem, the oxide got rid of my constipation. Now my constipation is back. Is it ok to take both the citrate/malate AND the oxide? I'd like to get the cardio/muscular/metabolic processes benefit of my magnesium by taking the more bioavailable form, but I cannot bare this constipation. Please help!!