Hi dr-Brahim and welcome to the forum!
I never heard of the Marshall protocol before reading your post, so I have made some research about it.
It is definitively a controversial protocol, and there is no solid proof that it can help in auto-immune diseases. A search for a scientific reference on Pubmed for it yield no results at all, so there has not been any study done. I have found a description and an analysis by a MD, at
https://sciencebasedmedicine.org/the-marshal-protocol/ . The use of prescription drug for hypertension, antibiotics, and avoidance of any vitamin D is not very appealing to me.
First, because vitamin D has been proven beneficial in some auto-immune diseases, like in Lupus.
Also, in my case, POIS causes me hypotension. So, it wouldn't be a good thing at all for me to take an angiotensin receptor antagonist like olmesartan or valsartan, that would make my hypotension worst ( taking an ARA is part of this protocol)
Here is the conclusion of the MD article I gave the link to: "So what do I make of the Marshall Protocal?
Unproven. Based on hypotheses that are almost certainly not true. Potentially harmful if it induces side effects from unneeded antibiotic uses or, more worrisome, from vitamin deficiency."
There are many safe alternative that have been successful for members here, so I would recommand experimenting with these rather than this protocol that appears to be still quite controversial.
You can take a look at my
POIS Types Chart to see what have been effective for other members ( no single method is effective for every POIS sufferers, so far, so you have to make some testing, with a safe approach, of course)