Fatigue has always been a part of my life as far back as I can remember. When I was in school (decades ago!) physical effort resulted in being "brain dead" for a few hours afterwards. I've also had diarrhea as far back as I can remember but it got much worse in my late teens. Cognitive dysfunction was through the roof, but I still managed to finish college with some effort. I was eventually diagnosed with both IBS and Chronic Fatigue Syndrome in my early 30's. Fast forward a decade and I'm passing out some two hours after eating, and reliably so. Visited quite a few doctors, did a bunch of tests and, with the exception of one, they were all OK. The only test that showed a potential screw up was Genova's (Metametrix at the time) GI Effects. It showed I had a huge overgrowth of Morganella Morgani in my digestive system. This bacteria is usually present in small amounts and as such causes no problems. After a course of Cipro, the watery diarrhea was gone together with said bacteria. But all the typical CFS symptoms were still present. No more passing out, just terrible brain fog some time after meals. A month or so ago, for whatever reason, I saw myself reading about intracranial hypertension. I had some of the symptoms but not all of them. But I was curious so I started digging deeper. I quickly found a study associating CFS with intracranial hypertension: Lumbar puncture, chronic fatigue syndrome and idiopathic intracranial hypertension: a cross-sectional study. Great, I finally had a potential explanation for my cognitive dysfunction! But what about passing out or that terrible brain fog sometime after eating? I started researching a simple treatment for intracranial hypertension. Lumbar puncture was out of the question, thank you very much! It didn't take long to find acetazolamide as a potential treatment, as this drug inhibits the production of cerebro-spinal fluid. It is also a non-potassium preserving diuretic (bad!) and may cause metabolic acidosis (bad!) So what do I do? I order the drug! While waiting for the drug to arrive, I continued reading about intracranial hypertension. For fun, I also decided to google "abdominal pressure intracranial pressure". My jaw dropped when I saw a bunch of results, one of them being "A proposed relationship between increased intra-abdominal, intrathoracic, and intracranial pressure". I was now waiting for the drug to arrive with a great deal of anticipation. I took my first dosage of acetazolamide and 30 minutes later I started to feel "funny". It was as if a had a ton of bugs crawling all over me. Although unpleasant, I wasn't alarmed as by now I was quite familiar with the potential side effects. After four or five days on the drug, I realized that I was no longer experiencing that terrible postprandial brain fog. Maybe just a little but nothing compared to what I was experiencing before. I've been on acetazolamide for a couple of weeks now and the good effect persists. I'm taking the lowest dosage available so I have enough for a couple more months. Before then, though, I plan to go to a neurologist with my findings to make my insurance company pay for the drug! Meanwhile, just a couple of days ago, I found out that I have a mild case of hypervitaminosis A. I don't supplement with any kind of pre-formed vitamin A so I am at a loss to explain the result. The funny thing is that hypervitaminosis A is strongly associated with intracranial hypertension (Serum vitamin A concentration is elevated in idiopathic intracranial hypertension). I need to dig deeper to try to make sense of this. PS. If you decide to go this route, please talk to your doctor first. Acetazolamide is potentially dangerous and may kill you. You've been warned!