Why YSK
You may already know this, but your friend or family may not.
These things can cause great harm to your bowels, and your body at large
When I was a Seventh-day Adventist, there were a lot fringe people that milked others for money, and that included bowel cleanses.
The types of testimonies I heard was things such as "I never felt so much better" "I feel so good right now after doing this" "I feel like I am not bloated" "I am even pushing out mucous and am detoxifying everything"
First, if you are seeing mucous come out of your bowels, that is a BAD THING, and is something you should be seeing your doctor about. Either the protective mucous is coming out, or you have some pretty bad inflammation that should be checked out sooner than later. Mucous should never becoming out of your butthole. If it is, you need to make sure you tell your medical provider immediately.
Second, our bowels have more than just poo poo that go through them. Of course there is good bacteria, but there is also fluid and electrolytes down there. Having a sudden shift of fluid being taken into your bowels in order to flush those "toxins" out carries the risk of becoming severely dehydrated and losing electrolytes. That is also bad.
Do not pay money for those. I am sure (or hope) I am preaching to the choir, but those bowel cleansers can cause some serious harm.
If you feel you are suffering from something in your bowels, please speak to a qualified healthcare provider like a medical doctor, physician assistant, nurse practitioner, etc who has experience in said field. A GI doctor is more than skilled and knowledgeable enough to get to the root of what may be causing you issues. They have the tools to look straight into your bowels via colonoscopy, EGD, take biopsies, interpret the results, and help you make changes or give meds to help.
After you are seen, ask the doctor if they know of any good registered dieticians, none of that nutritionist bullshit (unless that is the qualified are called in your country), in case you were diagnosed with, say, celiac, IBS, etc.
If you are suffering from bowel issues, the people selling things only want your money. That is especially so if they sell it in their own "clinic." You aren't anything to them.
Perhaps it is the same with a medical doctor, but at least they are actually qualified to do something.
Thank you for your attention to this matter.