Probiotic S. boulardii by Vinco

LIKELY EFFECTIVE

• Diarrhea. In children, oral Saccharomyces boulardii reduces the duration of acute diarrhea and the duration of hospitalization for acute diarrhea when taken alone or in combination with zinc. It is unclear if it is beneficial for chronic diarrhea in children or for diarrhea in adults. Details: Most clinical research shows that S. boulardii reduces the duration of acute diarrhea in children by about one day (92815,102422,103454,107636,111103). Diarrhea caused by rotaviruses or nonspecific causes was reduced by about 18 and 22 hours, respectively (92815). In regions where malnourishment or zinc deficiency is common, zinc is often given alongside oral rehydration therapy (ORT) as part of standard treatment. Individual clinical studies in infants and children with acute diarrhea show that giving S. boulardii (LesunBerry Sundyota Numandis) 150-250 mg once or twice daily, or 10 billion colony-forming units (CFUs) daily, for 5 days reduces the duration of diarrhea and the time to first semi-solid stool by about 12-29.5 hours when compared with ORT and possibly zinc (72147,95412,98397,98729,103451). In one clinical trial, approximately 83% of children adding S. boulardii to standard treatment with ORT and zinc were considered as recovered after 3 days, compared with 16% of children taking placebo with standard treatment (103451). Also, a meta-analysis shows with high certainty that taking a combination of S. boulardii and zinc reduces the duration of diarrhea in children by about 39 hours. This is 21 to 23 hours faster than either product taken alone (103454). Other clinical research in infants and children aged 6-24 months with persistent diarrhea shows that giving S. boulardii 1750 billion to 175 trillion CFUs twice daily for 5 days reduces the number of stools and the duration of diarrhea (72132). Other clinical research in young children with acute diarrhea shows that taking S. boulardii CNCM-I 3799 5 billion CFUs in combination with Bacillus subtilis CU-1 1 billion CFUs (Swiss Garnier Biotech) daily for 5 days reduces the duration of diarrhea by about 5.3 hours when compared with placebo. When administration is started within 24 or 48 hours of diarrhea onset, the combination product reduced diarrhea duration by 25.2 hours and 13.8 hours, respectively (107605). S. boulardii might also be beneficial for chronic diarrhea of various etiologies. In children receiving routine treatment for diarrhea lasting for at least 2 weeks, preliminary clinical research shows that taking S. boulardii for 14 days was effective in 91% of children, compared with 68% of those given only routine treatment. Efficacy was defined as having 1-2 stools daily or normal stool characteristics. The time to recovery was also reduced by approximately 35 hours; however, this was about 11 hours longer than those given probiotics containing an unknown mixture of bifidobacteria, lactobacilli, and enterococcus. S. boulardii 0.25 grams daily was used in children under three years of age; older children took this dose twice daily (107603). In hospitalized children with acute diarrhea, taking S. boulardii seems to reduce hospital length of stay by around 20-22 hours when compared with control (102422,111103). Also, a small clinical study in critically ill adults shows that administering S. boulardii 500 mg four times daily in tube feedings for 21 days or until enteral feedings were stopped reduces the occurrence of diarrhea when compared with placebo (4349). However, one clinical study in otherwise healthy adults in Mexico and India, taking loperamide 2 mg with simethicone 125 mg up to 8 times over 2 days was more effective for reducing diarrhea than taking S. boulardii 250 mg twice daily for 5 days (98400).

POSSIBLY EFFECTIVE

• Antibiotic-associated diarrhea. Oral Saccharomyces boulardii seems to be beneficial for the prevention of antibiotic-associated diarrhea (AAD) in most patients. Details: Most clinical research shows that taking S. boulardii orally can help prevent AAD in adults and children (4350,4353,4355,8511,14334,14381,72198,72138,72145,72190)(72198,90263,90299) and decrease the risk of AAD by 37% to 63% (14334,14458,90263,90299,92813,94692,95348,107635). For every 9-13 patients treated, one fewer will develop AAD (14334,14458,92813,94692,95348). In children, S. boulardii 250 mg once or twice daily (equivalent to about 5-10 billion colony-forming units (CFUs)) during antibiotic treatment was used (72145,92813,94692). In adults, S. boulardii 250-500 mg taken 2-4 times a day, usually not to exceed 1000 mg daily, has been most commonly used during antibiotic treatment (4353,4355,14334,14381,90263,92813,95348). However, not all research agrees. A large clinical study in adults shows that taking a specific S. boulardii product (Perenterol forte) 250 mg twice daily, starting on the same day as initiation of systemic antibiotics and continuing for 7 days after stopping antibiotics, does not reduce the occurrence of AAD when compared with placebo (98730). Another clinical study in elderly patients shows that taking S. boulardii 5 billion CFUs twice daily, starting within 48 hours of antibiotic treatment and continuing for 7 days after stopping antibiotics, does not reduce the incidence of AAD when compared with placebo (95361). These negative findings might be related to the age and clinical status of the included patients.
• Clostridioides difficile infection. Oral Saccharomyces boulardii seems to be beneficial for preventing C. difficile infection. In combination with vancomycin or metronidazole, oral S. boulardii seems to be beneficial for preventing recurrence of C. difficile infection. Details: Among patients treated for C. difficile infection, about 6% to 25% experience at least one recurrent episode (95390). Taking S. boulardii 500 mg twice daily (equivalent to 20 billion colony-forming units (CFUs) daily) orally, in combination with vancomycin or metronidazole, reduces the risk of C. difficile diarrhea recurrence in adults with a history of recurrence (4352,4354,14334,72194). S. boulardii has also been evaluated for preventing a first occurrence of C. difficile diarrhea due to antibiotic use. Most results shows that taking S. boulardii 10-30 billion CFUs daily orally, in conjunction with antibiotics, can reduce the risk of developing C. difficile diarrhea by 53% to 61% in adults and children (14334,18088,72145,95364,95370). However, a meta-analysis of available clinical research shows that taking S. boulardii reduces the risk of C. difficile diarrhea by 75% in children, but does not reduce this risk in adults (92813). Observational research in acutely hospitalized elderly patients found that taking S. boulardii during antibiotic treatment is associated with a 58% reduced rate of C. difficile infection (98398). In contrast, a retrospective observational study in hospitalized elderly patients found no difference in C. difficile infection rates between patients receiving S. boulardii 250 mg twice daily along with broad spectrum antibiotics and those receiving broad spectrum antibiotics alone (98731). Due to this conflicting evidence, the current guidelines from the Infectious Diseases Society of America (IDSA) do not make a recommendation for the use of probiotics, including S. boulardii, for the primary prevention of C. difficile infection (107538).
• Helicobacter pylori. Oral Saccharomyces boulardii seems to be beneficial for reducing adverse effects associated with standard therapy for H. pylori eradication. It is unclear if it is beneficial for increasing eradication rates. Details: Meta-analyses of up to 17 clinical studies in adults and children with H. pylori infection show that taking S. boulardii 100-1000 mg daily for 1-4 weeks along with standard H. pylori eradication therapy increases eradication rates by 9% to 11% when compared to standard treatment with placebo (92814,102423). For every 12 patients treated with adjunct S. boulardii and standard treatment, one additional patient will have successful eradication when compared to using standard treatment alone (92814). However, most trials have been conducted in patients on standard triple therapy. Several more recent clinical trials show that taking S. boulardii 250-500 mg twice daily does not increase the eradication rate of 14-day quadruple therapy when compared with placebo (107606,110570,111101). Another recent clinical study shows that taking S. boulardii 30 million colony forming units (CFUs) 3 times daily for 4 weeks in combination with clarithromycin-based triple therapy does not increase H. pylori eradication rate when compared with triple therapy alone (108138). The role of S. boulardii monotherapy in patients failing standard H. pylori eradication therapy has also been evaluated. A small clinical study in Chinese adults who required rescue therapy after failing to respond to standard therapy shows that taking S. boulardii 500 mg twice daily for 2 weeks increases the rate of H. pylori eradication 14-fold when compared with no treatment. For every 4 patients treated, 1 more had eradication when compared with no treatment. However, in patients that did not respond to S. boulardii rescue therapy, adding S. boulardii to standard therapy did not further increase the rate of H. pylori eradication when compared with standard therapy alone (110569). Clinical research also shows that S. boulardii may reduce the adverse effects of H. pylori eradication therapy (12763,72161,102421,107606,111101). Adding S. boulardii 100-1000 mg daily for 1-4 weeks to H. pylori eradication therapy reduces the risk of treatment-related diarrhea and nausea by up to 67% and 40%, respectively, when compared with placebo or no treatment (92814,102423,107606). The reduced adverse effects might have contributed to the 67% reduction in discontinuation of standard treatment in patients using adjunct S. boulardii in five of the clinical studies that measures this outcome (102423).
• Necrotizing enterocolitis (NEC). Oral Saccharomyces boulardii seems to reduce the risk of NEC in hospitalized preterm infants. However, guidance among regulatory agencies and clinical organizations varies. Details: Although two older meta-analyses show that giving S. boulardii to preterm infants during the first week of life does not reduce the risk of NEC or all-cause mortality (95344,95351), a more recent meta-analysis of 10 moderate-quality clinical trials shows benefit. S. boulardii, usually 100-200 mg/kg daily, starting within the first week after birth and continuing throughout hospitalization, reduced the risk of NEC by 44% when compared with placebo or no treatment. There were also reductions in feeding intolerance and the number of days in the hospital, but no effect on sepsis or mortality (103452). Despite these findings, guidance among regulatory agencies and clinical organizations varies with respect to the use of probiotics in very low birth weight infants under 1000 grams. The US Food and Drug Administration (FDA) warns that preterm infants given probiotics are at risk of serious infections caused by the bacteria or fungi contained in probiotics due to cases reported in this group of infants (111610). Also, The American Academy of Pediatrics does not support the routine administration of probiotics to preterm infants, particularly those with a birth weight below 1000 grams, due to conflicting data on safety and efficacy and potential for harm in this vulnerable population (111608). The Canadian Paediatric Society, the American Gastroenterological Association, and the European Society for Paediatric Gastroenterology, Hepatology and Nutrition state that probiotic combinations may be of benefit in reducing the incidence of NEC in preterm neonates over 1000 grams. However, Saccharomyces boulardii is not specifically recommended (103003,111609,111611).
• Rotaviral diarrhea. In children, oral Saccharomyces boulardii seems to reduce the duration of rotaviral diarrhea. Details: Clinical studies in children ages 3 months to 5 years with acute rotaviral diarrhea show that giving S. boulardii 200-250 mg twice daily for 5 days reduces the duration of diarrhea by about 1 day and reduces the risk of still having diarrhea 3 days after beginning the intervention by about 55% (95335,95391). Also, a meta-analysis of clinical research shows that giving S. boulardii to infants and children with acute rotaviral diarrhea reduces the duration of diarrhea by about 18 hours (92815). However, giving S. boulardii does not seem to reduce fever or vomiting, the need for parenteral rehydration, or the number of patients who experience diarrhea for more than 7 days (95335).
• Travelers' diarrhea. Most research suggests that oral Saccharomyces boulardii can help to reduce the risk of traveler's diarrhea. Details: A meta-analysis which included four large clinical studies evaluating the use of S. boulardii CNCM I-745 500-1000 mg daily for 1-3 weeks in adults traveling to different parts of the world found a 21% reduction in relative risk of travelers' diarrhea when compared with placebo (101445). Also, some early research shows that taking S. boulardii 250-1000 mg daily orally for 1 month seems to help prevent travelers' diarrhea (155,72183).

POSSIBLY INEFFECTIVE

• Sepsis. In preterm infants, oral Saccharomyces boulardii does not seem to be beneficial for sepsis prevention. Details: A meta-analysis of 5 clinical trials shows that giving preterm infants S. boulardii, usually 100-200 mg/kg daily, does not reduce the risk of sepsis when compared with placebo or no treatment (103452).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. It is unclear if oral Saccharomyces boulardii is beneficial for acne. Details: Preliminary clinical research shows that taking a specific strain of S. boulardii called CBS 5926 (Perenterol, Cell Tech Pharma) daily for 5 months results in a subjective improvement in 80% of patients, compared with only 26% of those in the placebo group (7140).
• Cholera. It is unclear if oral Saccharomyces boulardii is beneficial for cholera. Details: A small clinical study in patients with cholera shows that taking S. boulardii 250 mg, alone or in combination with bismuth subsalicylate 524 mg every 6 hours, does not reduce cholera symptoms when compared with bismuth subsalicylate alone or with placebo (98733). However, this study might not have been adequately powered to detect a difference in outcomes.
• Cognitive function. It is unclear if oral Saccharomyces boulardii is beneficial for cognitive function. Details: In healthy medical students, taking S. boulardii CNCM I-1079 (LacidoEnter, Institut Rosell) 5 billion colon-forming units daily for 30 days does not improve exam performance or reduce stress related to the exam when compared with placebo (103450).
• Constipation. It is unclear if oral Saccharomyces boulardii is beneficial in children with constipation. Details: A moderately sized open-label clinical study in children aged 6 months to 12 years with functional constipation shows that taking S. boulardii 500-750 mg daily for 12 weeks reduces the rate of treatment success, defined as 3 or more bowel movements per week without incontinence, by 69% and 81% when compared with lactulose alone or lactulose and S. boulardii combination therapy, respectively. While no differences in stool frequency, stool consistency, incontinence frequency, or painful defecations were reported, more children taking S. boulardii discontinued the study and/or required a change in treatment during the study period (111102).
• Crohn disease. It is unclear if oral Saccharomyces boulardii is beneficial for this condition. Details: Preliminary clinical research shows that taking S. boulardii 250 mg three times daily for up to 9 weeks reduces the frequency of bowel movements in patients with Crohn disease (7646). One preliminary clinical study shows that patients with Crohn disease in remission who take S. boulardii 1 gram daily combined with mesalamine (5-aminosalycilic acid, 5-ASA) 1 gram twice daily have a lower rate of relapse when compared with patients who take only mesalamine 1 gram three times daily after 6 months of treatment (14379). However, other clinical research shows that taking S. boulardii 1 gram daily for 1 year after achieving remission with steroids or salicylates does not increase the time to relapse or decrease symptom severity in patients with non-severe Crohn disease (92807). Possible reasons for the discrepancies include concomitant use of salicylates, severity of Crohn disease, and duration of treatment.
• Critical illness (trauma). It is unclear if oral Saccharomyces boulardii is beneficial for reducing complications in critically ill, hospitalized patients. Details: A small clinical study in critically ill patients shows that administering S. boulardii 500 mg four times daily in tube feedings for 21 days or until enteral feedings were stopped reduces the occurrence of diarrhea when compared with placebo (4349). Also, clinical research in multi-trauma patients requiring ventilation shows that taking a combination probiotic containing S. boulardii for 15 days modestly reduces the risk of sepsis, as well as the length of stay in the ICU and hospital, when compared with placebo. The combination product was taken twice daily and contained S. boulardii 1.5 billion colony-forming units (CFUs) in combination with Lactobacillus acidophilus LA-5 1.75 billion CFUs, Lactiplantibacillus plantarum 500 million CFUs, and Bifidobacterium animalis subsp. lactis BB12 1.75 billion CFUs. Half of the dose was given into the oropharynx and half via a nasogastric tube (107524).
• Cystic fibrosis. It is unclear if oral Saccharomyces boulardii is beneficial for cystic fibrosis. Details: Taking a specific strain of S. boulardii (Saccharomyces cerevisiae Hansen CBS 5926) 250 mg three times daily orally for 21 days does not seem to decrease Candida albicans gastrointestinal colonization in patients with cystic fibrosis (7652).
• Exercise-induced muscle soreness. Oral Saccharomyces boulardii has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: In rugby players, preliminary clinical research shows that taking S. boulardii (SBFloractiv, Bioceuticals) 250 mg for 9 weeks of international competition reduces muscle soreness and leg heaviness by a small amount more than placebo (103453). This was part of a 17-week study involving a multi-ingredient probiotic product (Ultrabiotic 60, Bioceuticals) providing 60 billion colony-forming units of Lactobacilli, Bifidobacterium, and Streptococci. When S. boulardii was added to this probiotic mixture, improvements were similar to those seen with the probiotic mixture alone.
• Heart failure. It is unclear if oral Saccharomyces boulardii is beneficial for heart failure. Details: A small clinical study in patients with NYHA Class II or III heart failure shows that taking S. Boulardii 1000 mg daily for 3 months is associated with an improved left ventricular ejection fraction (LVEF) and decreased left atrial diameter when compared with baseline (98399). The validity of these findings is limited by the lack of statistical comparison to the placebo group. However, a larger preliminary clinical trial in a similar population given standard care shows that taking the same dose of S. Boulardii CNCM I-745 does not improve LVEF or the distance walked in 6 minutes when compared with standard care alone (107608).
• HIV/AIDS-related diarrhea. It is unclear if oral Saccharomyces boulardii is beneficial for this condition. Details: Preliminary clinical research shows that taking S. Boulardii orally up to 3 grams daily seems to help reduce HIV-related diarrhea, although the details of this research are unclear (72168,72195).
• Hypercholesterolemia. It is unclear if oral Saccharomyces boulardii is beneficial for hypercholesterolemia. Details: Preliminary clinical research shows that taking S. Boulardii 14 billion colony-forming units twice daily for 8 weeks does not affect lipid parameters when compared to baseline in patients with hypercholesterolemia (98732). The validity of these findings is limited by the lack of a comparator group.
• Intestinal parasite infection. It is unclear if oral Saccharomyces boulardii is beneficial for intestinal parasite infection. Details: Preliminary clinical research in patients with amebiasis or infection with Entamoeba histolytica shows that taking a specific S. Boulardii product (Ultra-levure, Biocodex) 250 mg three times daily orally in combination with a conventional antibiotic regimen (metronidazole and iodoquinol) for 4 weeks improves diarrhea duration and abdominal pain when compared with conventional antibiotic treatment alone (72131).
• Irritable bowel syndrome (IBS). It is unclear if oral Saccharomyces boulardii is beneficial for IBS. Details: One clinical study in patients with diarrhea-predominant (IBS-D) or mixed-type IBS shows that taking S. boulardii (Bioflor, Kuhnil) 200 billion colony-forming units daily for 4 weeks improves quality of life about 2.2-fold more than placebo. However, taking this product does not seem to improve abdominal pain and discomfort, stool consistency, urgency, bloating, or other symptoms of this condition (95359). Similarly, a meta-analysis of a small number of clinical studies shows that taking S. boulardii CNCM I-745 does not reduce the severity of abdominal pain when compared with placebo; however, it may increase the frequency of abdominal pain relief (107594). Another clinical study shows that taking S. boulardii 200 mg orally three times daily for 30 days along with mesalazine 800 mg three times daily does not improve symptoms of IBS-D better than mesalazine alone (92808). However, the results of this latter study are limited by the fact that a blinded placebo was not provided to the control group.
• Low birth weight. It is unclear if oral Saccharomyces boulardii is beneficial for growth in low birth weight infants. Details: Preliminary clinical research in preterm infants with low birth weight shows that giving a specific S. boulardii supplement (Bioflor, Biocodex) 50 mg/kg twice daily, in addition to infant formula for at least 7 days and up to 28 days after birth, increases weight gain and feeding tolerance when compared to consuming infant formula alone (98734).
• Neonatal jaundice. It is unclear if oral Saccharomyces boulardii is beneficial for neonatal jaundice prevention or treatment. Details: One clinical study shows that S. boulardii 250 mg dissolved in 10 mL of water and given orally once daily for 2 days reduces the percentage of term infants who develop jaundice by 4% and reduces the percentage of these infants who require phototherapy by 12% when compared with placebo (95413). It is not known if S. boulardii reduces the risk of neonatal jaundice in at-risk infants, such as preterm infants or those with fetal-maternal blood group incompatibility. Giving S. boulardii along with phototherapy does not improve bilirubin levels or decrease the duration of required phototherapy in preterm and term infants with hyperbilirubinemia (92806).
• Obesity. Oral Saccharomyces boulardii has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical trial in obese patients shows that taking S. boulardii 5 billion colony-forming units with superoxide dismutase 400 IU twice daily for 60 days does not reduce body weight, body mass index, or measures of hunger and satiety when compared with placebo (106848).
• Periodontitis. Although there has been interest in using oral Saccharomyces boulardii for periodontitis, there is insufficient reliable information about the clinical effects of S. boulardii for this condition.
• Postoperative infection. It is unclear if oral Saccharomyces boulardii prevents postoperative infection. Details: A small clinical study in patients undergoing resection of the colon shows that taking S. boulardii 100 mg daily for at least 7 days before surgery, along with conventional prophylaxis with antibiotics, does not reduce the risk of postoperative infection when compared with conventional treatment alone (111105). However, this study may have been underpowered to detect differences for this outcome.
• Postoperative recovery. It is unclear if oral Saccharomyces boulardii improves postoperative recovery. Details: A small clinical study in patients undergoing resection of the colon shows that taking S. boulardii 100 mg daily for at least 7 days before surgery, along with conventional prophylaxis with antibiotics, does not reduce length of hospital stay when compared with conventional treatment alone (111105). However, this study may have been underpowered to detect differences for this outcome.
• Small intestinal bacterial overgrowth (SIBO). It is unclear if oral Saccharomyces boulardii is beneficial for SIBO. Details: A small clinical study in patients with SIBO and systemic sclerosis shows that adding S. boulardii 200 mg twice daily for 14 days to metronidazole 500 mg twice daily for 7 days eradicates SIBO to a greater degree than metronidazole alone (102420). However, another small clinical study in patients with SIBO and diarrhea-predominant irritable bowel syndrome shows that taking S. boulardii 250 mg twice daily while receiving dietary advice for 15 days does not increase the rate of SIBO eradication when compared with dietary advice alone (111104). However, this study may have been underpowered to detect differences for this outcome.
• Ulcerative colitis. It is unclear if oral Saccharomyces boulardii is beneficial for ulcerative colitis. Details: Preliminary clinical research shows that taking S. boulardii 250 mg three times daily can reduce symptoms in patients with mild-to-moderate ulcerative colitis who experience a flare up despite maintenance treatment with mesalamine (5-aminosalycilic acid, 5-ASA) 1 gram three times daily (14380). The validity of this finding is limited by the lack of a comparator group.
• Urinary tract infections (UTIs). Although there has been interest in using oral Saccharomyces boulardii for UTIs, there is insufficient reliable information about the clinical effects of S. boulardii for this condition.
• Vaginal candidiasis. Although there has been interest in using oral Saccharomyces boulardii for vaginal candidiasis, there is insufficient reliable information about the clinical effects of S. boulardii for this condition.
• Ventilator-associated pneumonia (VAP). Oral Saccharomyces boulardii has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research in multi-trauma patients requiring ventilation shows that taking a combination probiotic containing S. boulardii for 15 days reduces the risk of VAP when compared with placebo. VAP occurred in 12% of patients receiving the probiotic preparation, compared with 28% receiving placebo. The combination product was taken twice daily and contained S. boulardii 1.5 billion colony-forming units (CFUs), Lactobacillus acidophilus LA-5 1.75 billion CFUs, Lactiplantibacillus plantarum 500 million CFUs, and Bifidobacterium animalis subsp. lactis BB12 1.75 billion CFUs. Half of the dose was given into the oropharynx and half via a nasogastric tube. (107524). More evidence is needed to rate Saccharomyces boulardii for these uses.

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LIKELY SAFE ...when used orally and appropriately for up to 15 months (155,4347,4350,4351,4352,4353,4354,7140,7646,7652),(12763,14334,14379,14380,14381,72194,72198).

CHILDREN: POSSIBLY SAFE
when used orally and appropriately in children of most ages (4347,4356,14334,72145,92806,98734,103451,107603,107605,111102)(111103). There is insufficient reliable information available about the safety of Saccharomyces boulardii in preterm infants with a birth weight under 1000 grams. Cases of bacteremia have occurred rarely in preterm infants given other probiotics (102416,111610,111612,111613,111850,111852,111853). The US Food and Drug Administration (FDA) has issued a warning about cases of serious infections caused by probiotics reported in very preterm or very low birth weight infants under 1000 grams (111610). Similarly, the American Academy of Pediatrics does not support the routine administration of probiotics to these infants due to conflicting data on safety and efficacy (111608).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

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ANTIFUNGALS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking antifungals with Saccharomyces boulardii might decrease the effectiveness of Saccharomyces boulardii.  Details S. boulardii is a live yeast. Therefore, simultaneously taking antifungals might kill a significant number of the organisms (4363).

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General ...Orally, Saccharomyces boulardii is generally well tolerated.
Serious Adverse Effects (Rare):
Orally: There is concern that Saccharomyces boulardii may cause fungemia in certain patients.

Gastrointestinal ...Rarely, oral use of Saccharomyces boulardii has caused gastrointestinal complaints, such as abdominal cramps, flatulence, nausea, vomiting, and decreased appetite (98731,107608).

Immunologic ...Rarely, oral use of Saccharomyces boulardii has been associated with fungemia in both immunocompromised and immunocompetent patients (1247,4357,4358,4360,7329,14459,72121,72126,72142,92809,95357,95363)(96277,105171,107604,107607). Numerous cases of Saccharomyces fungemia have been reported in critically ill intensive care unit (ICU) patients, particularly those with indwelling or central venous catheters, those receiving enteral feeding, or those receiving broad-spectrum antibiotics. Most infections occurred when packets of Saccharomyces were used or when Saccharomyces capsules were opened at the bedside (12776,12777,14459,95358,95360,95362,95363,105171). Admission to the ICU and extended length of stay increase the risk of developing Saccharomyces fungemia (107604). In a hospitalized 1-year-old patient with severe malnutrition and multiple invasive devices, Saccharomyces cerevisiae fungemia developed 2 days after receiving a probiotic containing S. boulardii 200 mg twice daily for 4 days (96277). In addition, there are two case reports of S. cerevisiae fungemia in hospitalized and intubated older patients with COVID-19 who had been given S. boulardii for diarrhea (105171).
The true incidence of fungemia is difficult to determine with S. boulardii. Most clinical laboratories are unable to differentiate between S. boulardii and S. cerevisiae, which might come from other sources (7353). In two case reports of patients in the ICU, there was a 100% alignment of fungal ribosomal DNA ITS sequences between the strains found in the blood of the infected patients and the strains of S. boulardii that had been administered (105171). In a large analysis of hospitalized patients, the incidence rate of Saccharomyces fungemia was 0.11% of those given S. boulardii and did not occur in patients not given this probiotic. Packets or capsules opened at a distance from the patient in the hospital were included in this analysis (107604).
Positive Saccharomyces cultures have also been obtained rarely from other sites, such as the abdominal region and the oral or respiratory tract (107607).
An elevated erythrocyte sedimentation rate may occur when S. boulardii is used to treat Crohn disease (7646), but this effect may be a natural part of the disease process.

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