Magnesium and Azythromycin

Here's the real deal on magnesium and azithromycin:

1) Macrolide antibiotics (i.e., azithromycin, clarithromycin, and erythromycin) deplete magnesium (Mg).

Nearly every med prescribed for CF depletes Mg, which further lowers body pH, including lowering pH of the lungs making them more acidic. Many bacteria, fungus and cancer thrive in an acidic environment.

2) Mg inhibits antibiotic efficacy. You can't take Mg and certain antibiotics *together* because they compete for the same receptor site on the cell membrane, and magnesium will win, cutting antibiotic efficacy. So you must follow a rule of thumb:

Take antibiotic, wait 2 hours.
Take Mg, wait at least 4 hours before next antibiotic dose.
The exception is Cipro; you must wait 6-7 hours after taking Mg before you can take another dose of Cipro.

My son takes Zithromax before bed, and takes Mg throughout the day to avoid interaction. I do the same whenever I have to take AZM.

3) Mucoid pseudomonas is more likely to grow in a Mg-deficienct host. Additionally, the mucoid PA will likely be resistant to aminoglycoside antibiotics (i.e., gentamycin, tobramycin, amikacin). Studies suggest this is reversible when Mg-deficiency is reversed (and it did prove reversible in my son, eventually even eliminating mucoid PA).

4) If you take aminoglycoside antibiotics during Mg-deficiency, you run a greater risk of ototoxicity and vestibular damage. There is some evidence that supplementing Mg at the first sign of ototoxcity may slightly attenuate the damage, but not completely reverse it.

5) During Mg-deficiency, taking macrolide antibiotics alone (and taking macrolides along with antifungals) increases risk of developing prolonged QT waves and Torsade de points, which can result in cardiac death.

Therefore, some authors have stated in cardiac journals that they feel it's crucial to have your Mg levels in the high-normal range before taking macrolide antibiotics.

But how many CF doctors know or even check Mg status?

Perhaps the reason that Pulmozyme (rhDNA) works better in a Mg-sufficient host is that Mg helps regulate opening-closing of the CFTR. With better channel gating, mucus is less likely to be as thick... Maybe. I don't know. But that's my guess anyway. Magnesium is responsible for so many things at the cellular level, why question it... just take it.

Written by Kim Payne (c)2007


A number of people have written me after reading this page to ask how much one should take and what type, etc. Here is a link to the dosing formula that Kim Payne has previously recommended:
Formula to Calculate Magnesium Daily Requirement .
Further down that page is info on
How to Take Magnesium and What Kind of Magnesium to Take .

Updated 31 May 2008

From a site I ran years ago called Health Gazelle. Kim Payne was a parent of a person with CF. Her son was an adult and she was very knowledgeable about some things. Magnesium supplementation was one of them.

It was posted to Health Gazelle with permission from the original author, Kim Payne. It probably originally came from an email to an email list we were both on.

See also: 14 Drugs That Deplete Magnesium