 A worldwide leader in microbiome health for over 40 years, Dr. O'Hara's Probiotics is an enriched full-spectrum probiotic system fermenting multiple strains of probiotic bacteria and nourishing prebiotics. The result? Transformative postbiotic metabolites that maintain and support the biodiversity of flora in your gut for optimal digestion, gut-brain, and immune health. Dr. O'Hara's. Certified Vegetarian.