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Head-to-head evidence comparison — which supplement is right for you?
Probiotics wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
4 of 4 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
30 of 39 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both Passionflower and Probiotics have evidence — compare verdict strength side-by-side.
250-500mg extract (or 2g dried herb)
For anxiety: as needed, For sleep: 30-60 minutes before bed
Standardized extract capsules
10-20 billion CFU
With or without food (strain-dependent), Same time daily for consistency
Capsules with multiple strains
30 min - 2 hours
30-60 minutes
30-60 minutes
2-4 weeks
4-8 weeks
4-8 weeks
First 1-2 weeks
Herbal Remedies and Their Possible Effect on the GABAergic System and Sleep
Nutrients (2021) · Systematic review
Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter that plays a major role in controlling different vigilance states.
Passiflora incarnata in Neuropsychiatric Disorders-A Systematic Review
Nutrients (2020) · Systematic review
Passiflora incarnata may be helpful in treating some symptoms in neuropsychiatric patients.
Herbal medicine for depression and anxiety: A systematic review with assessment of potential psycho-oncologic relevance
Phytotherapy research : PTR (2018) · Systematic review
Overall, 45% of studies reported positive findings with fewer adverse effects compared with conventional medications.
Preventive Effect of Probiotics on Oral Mucositis Induced by Cancer Treatment: A Systematic Review and Meta-Analysis
International journal of molecular sciences (2022) · Meta analysis · n=708
Three trials using Lactobacilli-based probiotics reported that the incidence of oral mucositis in the probiotic group was significantly low (risk ratio [RR] = 0.84, 95% confidence interval [CI] = 0.77−0.93, p = 0.0004).
Probiotics for treating acute infectious diarrhoea
The Cochrane database of systematic reviews (2020) · Meta analysis · n=12127
Effect size was similar in the sensitivity analysis and marked heterogeneity persisted.
Probiotics for the prevention of Clostridium difficile-associated diarrhea in adults and children
The Cochrane database of systematic reviews (2017) · Meta analysis · n=9955
A complete case analysis (i.e. participants who completed the study) among trials investigating CDAD (31 trials, 8672 participants) suggests that probiotics reduce the risk of CDAD by 60%.
Based on meta-analysis of 198 subjects noting insufficient RCT data for definitive conclusions. Effectiveness limited by small sample sizes and study quality limitations. Drowsiness is primary dose-limiting side effect.
Based on meta-analyses showing benefits for IBS and digestive symptoms. Effect sizes varied considerably between studies with low to very low certainty of evidence. Initial GI symptoms common when starting but typically resolve within 1-2 weeks.
AI-estimated from published studies. Interpret as directional guidance.
Probiotics has a higher evidence score (9/10 vs 5.5/10) and wins in 2 of 3 categories.
For reduce anxiety & stress, Passionflower has a higher relevance score (85 vs 52).
No known interactions between Passionflower and Probiotics have been documented in our database. However, always consult a healthcare provider before combining supplements.