After much research, I learned that the stomach problems I have experienced for MUCH too long were most likely due to a case of Clostridium Difficile. The condition is caused by an extreme overgrowth of Clostridium bacteria in the lower intestine. This overgrowth is generally brought on by a lack of other naturally-occurring, beneficial bacteria in the intestines, which are necessary for normal bowel function. This lack can be caused by anything from a pre-existing illness to a microbial exposure to high stress, but it is usually the result of having taken antibiotics. Simply put, antibiotics kill bacteria no matter if that bacteria is "bad" or "good". There certainly are times in our lives when we may need to take antibiotics for one reason or another, so afterward, the intestines must be replenished with their normal level of beneficial bacteria. Oftentimes the intestines do this job on their own. Sometimes they don't, and Clostridium bacteria can over-produce. That is how the problem begins. As Clostridium Difficile flourishes, it produces toxins that are released through the digestive tract. The result is progressively worsening irregularity with any combination of abdominal cramping, bloating, diarrhea, constipation, nausea and/or vomiting. The hallmark sign of Clostridium Difficile is particularly foul-smelling gas flatulence, which reeks with the odor of sulphur, rotten eggs and ammonia. This gas is constant, virtually uncontrollable and actually feels HOT when it is expelled. It can oftentimes cause irritation by itself and is extremely embarrassing, because it is so frequent, impossible to stop, nasty-smelling and sometimes accompanied by "leakage". An overgrowth of Clostridium bacteria can be difficult to correct, because it will form spores that attach themselves to the lining of the intestines. These spores are a cunning defense mechanism. . .they encapsulate and protect the Clostridium bacteria so it can survive an antibiotic treatment for Clostridium difficile! But this is where Sacharomyces Boulardii really does its job. It not only helps kill off unnecessary microbes in the intestines, but it also keeps them from attaching to the lining! If you think you may have a case of Clostridium Difficile, please do your own research to learn the best way to combat it, and be sure to consult your doctor. ;) To say the least, I have found Sacharomyces Boulardii to be a VERY "friendly" bacteria that is vital in the correction of Clostridium Difficile. I take one at the crack of dawn every morning (on an empty stomach is best) with a full glass of water along with my other regular probiotics (Vitacost 15 - 35) and my multivitamin. I try to avoid eating anything for at least an hour afterward, which helps ensure good absorption (avoiding stomach acid). I do try to take Sacharomyces Boulardii and my other regular probiotics anytime that I am on antibiotics. . .though they need to be taken a couple of hours beforehand or afterward to keep the antibiotics from killing them. But I ALWAYS take them for at least a couple of months beyond my having been on antibiotics. Also, Sacharomyces Boulardii is highly beneficial for other issues. . .even maintaining a clearer complexion! I will never be without it. P.S. To help keep it active for as long as possible, go ahead and store it in the refrigerator. ;