My Mayo experiences:
Earlier this week I tried a bisacodyl and soap (B&S or "Clayton" ) enema in my quest to evaluate options for my IBS management menu, and today I gave the Mayo enema a test run.
This is really the second time I tried the Mayo. I took one a few months ago on a personal dare. That one was 1 quart full-strength, and I wasn't exactly constipated at the time. Today I was trying it for a different reason and things were more backed up.
I used "half strength" recipe - 1/2 cup sugar, 1/4 cup soda, 1 quart water. Added soap for a bit of an extra kick - 1Tbsp soap goo, which is about 2 teaspoons castile equivalent. I credit Agasmic with the half-strength idea, gynocamastia with the soap addition, barb691/ccg for the use of brown sugar and Marlene with the rinse recommendation. I've tried this with white sugar before, but this one was half white/half brown. Including some brown sugar seems to make the enema much more effective and faster. I'm not sure why, but it does. I use half brown/half white because I can mix the two together and it makes it easier to dissolve the sugar in the water because it doesn't clump.
Speaking of dissolving - many recipes call for mixing this in two containers, one with sugar and one with the soda, then pouring them in the bag at the last minute. If you move reasonably fast I haven't noticed a problem with mixing it all together in one bin, and it's easier to carry one container with the measured sugar and soda to the bathroom rather than trying to manage separate ones.
Even at half strength you need to keep the solution (really a mix of a solution and suspension) agitated or it won't stay mixed up. I mixed it right before hanging the bag, and by the time I had gotten myself into position (knee-chest) the soda had already started to settle out. I grabbed the hose and swung the bag from side to side a bit, and this allowed the soda to work its way down into the tube and up my ass. Some posts recommend a colon tube, but I used a rectal nozzle (Model S) because there was no way I'd get a colon tube very far up and I didn't want to have it slip out because I probably would only get it in 2-3 inches.
This is a fast enema. It has a fast reaction time and you really should take it at a fast flow so it all gets in before the action starts. I hung my bag from the shower curtain rod, put my chest on the towel, flicked the clamp and prepared to hold on for dear life. It wasn't quite that bad at first, or really at second (but that could be because of my half-strength mix). It didn't feel like water, there was some urgency and burning right away, probably from the hypertonic solution (isotonic would use only about 1/4 of the soda of my half-strength solution). After the bag gurgled dry I rolled onto my right side to allow the enema to get through my whole colon, slipped a buttplug in place, and waited. I didn't have to wait long before things got more intense, they started ramping up within a minute. All told, with a plug in place and my cheeks clamped down I lasted to the 7 minute mark. The expulsion, while fast and thorough, wasn't quite as smooth as the expulsion from the B&S/Clayton enema, but it definitely did the job of cleaning me out. A few minutes after the initial expulsion was done my colon started to cramp up and I had a second strong expulsion. The cramps at this stage were the strongest of the whole enema. While I wasn't doubled over or nauseous, this was more cramps than your usual 2-quarts of strongish soapsuds. A few minutes after the second expulsion there were more cramps (but much less strong) and a third expulsion.
A rinse enema is highly recommended. Because of the hypertonic nature of the enema I would imagine you'd get many repeat visits to the toilet over the next couple of hours if you didn't. The rinse will be a toe-curler, as your bowels will still be contracting, but worth it. I did mine after the third expulsion, but I might have wound up cleaner had I waited for a fourth.
The hypertonic nature of the enema also means that you need to hydrate before and after. I'm too lazy to calculate the osmolarity of the solution, but it does pull water out of you. Like a Fleet's you also should be concerned if it doesn't come out within a reasonable time (say two hours) because your body can absorb too much sodium if it stays in.
Cleanout efficiency was pretty good. There weren't any large chunks in the return from the rinse, whereas I usually have some when I use 2 quarts of weak soapsuds for the first enema. The cleanout was not quite as good as the 2-quart B&S/Clayton enema, but close and any difference might be eliminated if the Mayo enema was doubled so there was an equivalent amount of solution. Afterwards even with the rinse my gut was left "worked up" and it took a while to settle down, more so than usual with SSEs or the bisacodyl and soap enema. Note that this might be from my IBS, but even so this probably isn't the enema to take if you want to relax your colon. It did a great job of getting everything out and all the bloating went away.
Other than the sticky factor from the sugar cleanup was easy, soap on the nozzle and rinsing the rest of the equipment in hot water got it close enough to clean for me. Watch out for drips, though they wipe up easily enough they'll be sticky if you miss. I don't want to think about cleanup if the nozzle slips out or you have a blowout!
Interesting things I noticed:
The Mayo enema generates gas, which will cause any solids in the return to float instead of sinking in murky gloom. It was a surprise to look down and see exactly how much crap was inside me. I guess that's because of all the fiber I'm taking, and probably also explains why my appetite starts to go away pretty quickly once the bowels stop moving.
The bisacodyl and soap was more "regular" in the cramping. It started out a few minutes in with about one a minute, then slowly got faster. The Mayo was less predictable. The cramps started faster, but would come more often and with more of an irregular break in between. This may have just been a "that day" thing, so it would be interesting to see if that happens next time.
While I didn't get an erection from either the Mayo or B&S/Clayton I did get quite a bit of precum. These powerful enemas seem to be stimulating something in my pelvis, though I'm not sure what.
Conclusion: it's not going to be my go-to enema, but the Mayo is very effective and definitely adds a bit of variety, at least in the half-strength quart version. It isn't an enema I'd take to help calm down my gut, but it's great at kicking things out, and there are those days when I just want things out and if along the way I get my "ass kicked" it just lets me know that I'm taking care of the problem. The full-strength quart version (1 C sugar, 1/2 C soda) is likely more in the punishment camp (especially if made with brown sugar), though that could be fun too given the right setting and less of a rough ride than Susie's recipe. Much more burning, and while the cramping intensity was about the same the onset was faster and the duration longer in the full strength version. I'd strongly recommend an inflatable nozzle for the full-strength quart version so you don't have unexpected cleanup. The sugar means that anything you spill will get sticky, so this is an enema that is best taken somewhere with hard surfaces that are easy to clean up just in case there's some drips or leakage. I guess some day I'll probably try a milk and molasses, but the Mayo is very effective and seems as though it would be much easier to clean up after. PS - If you're really masochistic the recipe for a 2 quart version would be 2 cups sugar 1 cup soda and 2 quarts water, with 2-4 teaspoons of castile soap, but I don't think I'll go there.
NOTE: this is probably not a good enema to use if you are diabetic or have kidney issues, especially if you are going to be retaining it more than a few minutes. There is a lot of sodium and sugar in here, and while the large intestine isn't optimized for absorbing nutrients and electrolytes it can. On the flip side note that the adverse effect noted was in someone who was critically ill, had renal failure, and retained the enema for 12 hours. The authors even note that complications "have not been previously reported."