Search the world's information, including webpages, images, videos and more. Methods: In this double-blind, placebo-controlled, randomized clinical trial, 173 participants (26.8±0.9 y [mean ± SEM]) who self-identified as having seasonal allergies received either a probiotic (2 capsules/day, 1.5 billion cells/capsule) or placebo during spring allergy season for 8 weeks. Google has many special features to help you find exactly what you're looking for.