What are the advantages or disadvantages of taking more than the recommended dose of probiotics while taking concurrent aerobic and anaerobic antibiotics?

From the Guidelines

Taking more than the recommended dose of probiotics while on both aerobic and anaerobic antibiotics is not recommended, as it may cause unnecessary side effects without providing additional benefits. The American Gastroenterological Association (AGA) suggests the use of certain strains and strain combinations of probiotics in the prevention of C difficile infection, but the evidence is based on standard dosages, not excessive ones 1.

Key Points to Consider

• The effectiveness of probiotics during antibiotic therapy depends more on timing than quantity, with the recommendation to take probiotics at least 2 hours before or after antibiotics to prevent the antibiotics from killing the beneficial bacteria.
• Common effective probiotic strains during antibiotic treatment include Saccharomyces boulardii, which may have a beneficial effect on cessation and recurrence of diarrhea, as shown in a study with 134 patients (RR, 1.33; 95% CI, 1.02–1.74) and (RR, 0.59; 95% CI, 0.35–0.98), respectively 1.
• Excessive doses of probiotics may cause digestive discomfort, including bloating, gas, or diarrhea, and some individuals might experience more severe side effects like headaches or allergic reactions.
• The AGA recommends specific probiotic strains and combinations for the prevention of C difficile infection, including S boulardii, or the 2-strain combination of L acidophilus CL1285 and Lactobacillus casei LBC80R, but these recommendations are based on standard dosages and the overall quality of evidence is rated as Low 1.

Recommendations for Probiotic Use

• Stick to the recommended probiotic dosage on the product label, typically ranging from 1-10 billion CFUs daily for most commercial products.
• Choose probiotic products containing effective strains such as Saccharomyces boulardii, Lactobacillus acidophilus, or Bifidobacterium species.
• Consider the timing of probiotic intake in relation to antibiotic use, aiming for at least a 2-hour gap to maximize the survival of beneficial bacteria.

From the Research

Advantages and Disadvantages of Taking More Than the Recommended Dose of Probiotics

• The current evidence does not provide a clear answer to the question of taking more than the recommended dose of probiotics while taking concurrent aerobic and anaerobic antibiotics 2, 3, 4, 5, 6.
• However, some studies suggest that higher doses of probiotics may be more effective in preventing antibiotic-associated diarrhea (AAD) and Clostridium difficile-associated diarrhea (CDAD) 2, 4, 6.
• A meta-analysis found that probiotics reduced the risk of CDAD by 60% and AAD by 44% 4, 6.
• Another study found that probiotics reduced the risk of adverse events by 17% 4.
• However, a multicentre randomized placebo-controlled trial found no significant evidence of a beneficial effect of a specific probiotic formulation in preventing AAD in an elderly population 5.

Dose-Response Relationship

• A review of dose-responses of probiotics in human studies found that the dose-response relationship varies depending on the outcome being measured 2.
• For AAD, the findings suggest a positive correlation between dose and AAD risk, with higher doses being more effective 2, 4.
• However, for other outcomes such as immune markers, general health, and bowel function, no clear dose-response relationship was observed 2.

Safety and Efficacy

• The short-term use of probiotics appears to be safe and effective when used along with antibiotics in patients who are not immunocompromised or severely debilitated 4.
• However, further research is needed to fully understand the safety and efficacy of probiotics in different populations and settings 3, 4, 5, 6.