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Date of last update: 9/5/2017.

Forum Name: Pharmacy & Drug Topics

Question: magnesium citrate or phospha soda

 susieQ1 - Sat May 24, 2008 5:41 pm

My GI dr has told me that I could use either one of the above for my colonoscopy prep. I am 65 & have read a lot of negative things about phospha soda. I do have a problem with magnesium & seizures so I'm having trouble deciding what to try. The other preps have been ruled out because of my allergic reaction to them. I'm concerned about sodium content & kidney failure. Altho. as far as I know I do not have kidney problems I would like to keep it that way.

Which of the two has the least amount of sodium? I know you can't tell me which to take I would like all the info I can get on these. Thanks.
 John Kenyon, CNA - Tue Jul 29, 2008 10:53 pm

User avatar Hello -

I'm not sure how your seizure problem relates to magnesium, but magnesium citrate is only about 11% magnesium by volume, and with the large amounts of water which go with taking this, it should actually introduce very little magnesium into your bloodstream, since the whole purpose is to purge your bowel anyway. It is definitely my personal choice over phosphate of soda, which can be pretty unpleasant.

As for kidney problems, while magnesium citrate is contraindicated in people with existing kidney disease, it is not known to cause it, at least not in the amounts found in normal useage.

I hope this is helpful to you. Good luck with this.

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