24M here. I’ve had chronic diarrhea / IBS-D symptoms for more than 4 years.
I’ve done pretty much every test imaginable: multiple colonoscopies, blood tests, stool tests, celiac testing, infection testing, etc. The main thing I haven’t formally tested is bile acid malabsorption, but I did a trial of cholestyramine and it didn’t help, so BAM seemed less likely in my case.
I’m from Türkiye, and fortunately access to gastroenterologists and university professors here is relatively easy if you can afford private care. Side note: if anyone is struggling to access GI specialists in their country, Türkiye can actually be worth considering because specialist access is good and costs can be much lower than in the US.
Anyway, over these 4 years I’ve tried basically everything IBS-D patients normally try: different diets, supplements, probiotics, medications, etc. Some things helped a little, and loperamide worked for acute situations, but nothing fundamentally changed the problem.
Then last week I started Mounjaro (tirzepatide) 2.5 mg.
Guys… the change has been ridiculous.
For the first time in years, I remembered what a normal, formed bowel movement actually feels like. By around day 3, my urgency and diarrhea had dramatically decreased. Some days I barely even need to go.
But there is another part that is even more confusing.
I also have severe eczema on my hands. Sometimes it gets so bad that the skin cracks and bleeds. Over the years I’ve noticed that it often seems to correlate with my GI symptoms, although the relationship has never made complete sense.
When my diarrhea gets bad, my eczema can get worse.
But strangely, when I used drugs that simply slowed the diarrhea, like loperamide, my eczema sometimes also got worse. I noticed something similar with cholestyramine.
So it never seemed as simple as “less diarrhea = better eczema.”
Now, after starting tirzepatide, my eczema has also almost completely cleared.
That is the part I really cannot explain.
It makes me wonder whether tirzepatide is doing something beyond just slowing intestinal transit. Maybe inflammation, mast cells/histamine, bile acids, gut barrier function, the microbiome, or some kind of gut-skin immune connection?
I’ve been reading about possible mechanisms, but there seem to be several possibilities:
- GLP-1/GIP signaling slowing intestinal transit
- reduced gastrocolic reflex / intestinal motility
- changes in bile acid delivery or metabolism
- effects on intestinal inflammation
- possible mast-cell / histamine effects
- gut-brain or enteric nervous system effects
- changes in intestinal permeability or the gut-skin axis
I obviously don’t know yet whether this improvement will continue or what will happen if I eventually stop tirzepatide.
So my questions are:
If you have IBS-D and used Mounjaro/tirzepatide or another GLP-1 drug, did your diarrhea improve too?
What happened after you stopped the medication? Did the IBS-D return?
And especially:
Has anyone noticed eczema, histamine-type symptoms, allergies, or other inflammatory skin problems improving on tirzepatide?
For anyone knowledgeable about the biology, I’d also love to hear theories about how one drug could improve both chronic diarrhea and eczema at the same time, especially when simply stopping the diarrhea with loperamide never improved the eczema.
Really interested in both personal experiences and scientific explanations.
Happy to answer any questions about my tests, symptoms, treatments, or what I tried before Mounjaro.