IBS is a term used to describe quite a variety of symptoms of gut malfunction, and a difficult one to really pinpoint and diagnose. After having eliminated all other possible physiological conditions you could suffer from (subjecting you to a battery of tests including a colonoscopy to set you back more than just a few bucks), doctors will pronounce that you have IBS (C, D or A). You don't have to exhibit pain or cramps, specifically, for this "diagnosis", for many people it's more about discomfort than anything else. Anyhow, I have had it too since my twenties - the C-type.
My particular symptoms relate to spasm of the rectosigmoid junction, where it clamps shut during evacuation even though the sigmoid may be full and ready to unload some more. The faecal matter is not necessarily hard either, it just won't come out unless I strain heavily. Which in turn produces more spasm, more constricting closure, more discomfort. The worst part is that the spasm continues for hours after an attempt to defecate, which is a terribly uncomfortable feeling of a continuous urge to evacuate, but no show when I go to the toilet. Strictly speaking this is not constipation (hard, compacted faeces), the gut just won't evacuate anything unless it is liquid. Hence, enter the enema.
Long story short, a daily morning enema (large volume, 2.5 quarts and up) has sorted the problem. No more symptoms. In fact, the muscle toning resulting from the enemas has given my gut a substantial level of "re-training" in that I can go normally too, and don't suffer the symptoms like I used to. Nowadays I do regular coffee enemas, epsom salts (I need Magnesium supplementation due to a rigorous weekly workout routine, so this works well) as well as the occasional lemon, or garlic, or saline, or bicarbs enema. Soap also, but it tends to irritate my gut and therefore I limit the frequency of SSE's.
Have been doing this for many years, and I'm fit as a fiddle, healthy as a horse. Keeping me younger-looking too (most people estimate my age in the mid-forties, and I am actually late-fifties). I can really recommend this regime, IBS or not. Oh, yeah, and let's not forget the pleasurable side of enemas.... 😈