Probiotics side effects
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Common Probiotics Side Effects and Adverse Reactions
Probiotics are generally considered safe for most people, but several studies highlight that they can cause a range of side effects. The most commonly reported issues include gastrointestinal symptoms such as abdominal pain, bloating, gas, and diarrhea. In some cases, skin complications, inflammation of the endocardium (the inner lining of the heart), and metabolic disturbances have also been observed. There is also a risk of systemic infections, especially in vulnerable populations, and concerns about gene transfer from probiotics to normal gut bacteria, which could potentially spread antimicrobial resistance 129.
At-Risk Populations for Probiotic Side Effects
Certain groups are more susceptible to adverse effects from probiotics. These include infants, elderly individuals, hospitalized patients, and people with weakened immune systems due to genetic or acquired conditions. For these groups, the risk of systemic infections and other complications is higher, and careful evaluation of the risk-benefit ratio is recommended before using probiotics 12.
Probiotics and Gastrointestinal Side Effects in Specific Conditions
In patients with inflammatory bowel disease (IBD), studies show that probiotics may increase the risk of gastrointestinal side effects compared to placebo, with abdominal pain being the only symptom reaching statistical significance. However, the overall risk for side effects was not significantly higher than placebo for most symptoms . In cancer patients undergoing chemotherapy or radiotherapy, probiotics have been studied for their potential to reduce treatment-related gastrointestinal side effects such as diarrhea, mucositis, constipation, nausea, and vomiting. While many studies report positive effects, the data is heterogeneous, and firm conclusions about safety and efficacy are still lacking 456.
Probiotics and Drug-Related Side Effects
Probiotics are being explored as adjuncts to reduce the side effects of various drugs, including those used in cancer therapy and for Helicobacter pylori eradication. Some studies show that probiotics can help maintain gut microbiota balance and reduce the incidence of gastrointestinal adverse events during drug treatments. However, the effectiveness and safety can vary depending on the probiotic strain and the patient population 78.
Rare but Serious Risks: Infections and Immune Reactions
Although rare, probiotics can cause serious infections, particularly in immunocompromised individuals. There have been reports of probiotics leading to systemic and local infections, allergic reactions, and even facilitating the spread of antimicrobial resistance genes. These risks, while uncommon, highlight the need for caution, especially in vulnerable groups 12.
Conclusion
While probiotics are widely used and generally safe for healthy individuals, they can cause side effects, particularly gastrointestinal symptoms. Vulnerable populations such as infants, the elderly, hospitalized, and immunocompromised individuals are at higher risk for more serious adverse effects, including infections. The safety profile of probiotics varies depending on the strain, dose, and patient condition, so careful consideration and consultation with healthcare professionals are advised before use, especially in at-risk groups 1239.
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