That is long enough, but sometimes its hard to tell if something is working somewhat or not.
There actually is a new study showing one strain to be unhelpful.
BMC Gastroenterol. 2010 Feb 10;10(1):16. [Epub ahead of print]
A candidate probiotic with unfavourable effects in subjects with irritable bowel syndrome: a randomised controlled trial.
Ligaarden SC, Axelsson L, Naterstad K, Lydersen S, Farup PG.
ABSTRACT: BACKGROUND: Some probiotics have shown efficacy for patients with irritable bowel syndrome (IBS). Lactobacillus (L.) plantarum MF1298 was found to have the best in vitro probiotic properties of 22 strains of lactobacilli. The aim of this study was to investigate the symptomatic effect of L. plantarum MF1298 in subjects with IBS. Primary outcome was treatment preference and secondary outcomes were number of weeks with satisfactory relief of symptoms and IBS sum score. METHODS: The design was a randomised double blind placebo-controlled crossover trial. 16 subjects with IBS underwent two three-week periods of daily intake of one capsule of 1010 CFU L. plantarum MF 1298 or placebo separated by a four-week washout period. RESULTS: Thirteen participants (81%; 95% CI 57% to 93%; P = 0.012) preferred placebo to L. plantarum MF1298 treatment. The mean (SD) number of weeks with satisfactory relief of symptoms in the periods with L. plantarum MF1298 and placebo were 0.50 (0.89) and 1.44 (1.26), respectively (P = 0.006). The IBS sum score was 6.44 (1.81) in the period with L. plantarum MF1298 treatment compared with 5.35 (1.77) in the period with placebo (P = 0.010). With a clinically significant difference in the IBS sum score of 2 in disfavour of active treatment, the number needed to harm was 3.7, 95% CI 2.3 to 10.9. CONCLUSIONS: This trial shows for the first time an unfavourable effect on symptoms in subjects with IBS after intake of a potential probiotic. The trial registration number: Clinical trials NCT00355810.
PMID: 20144246 [PubMed - as supplied by publisher]
This one is the strain in digestive advantage
Methods Find Exp Clin Pharmacol. 2009 Dec;31(10):655-9.
Effects of a proprietary Bacillus coagulans preparation on symptoms of diarrhea-predominant irritable bowel syndrome.
Accelovance Inc., Peoria, Illinois, USA. email@example.com.
Symptoms of irritable bowel syndrome (IBS) have a profound impact on quality of life for many patients and current treatments are sometimes unsatisfactory. This controlled pilot study was conducted to evaluate effects of the proprietary GanedenBC(30) (Bacillus coagulans GBI-30, 6086) probiotic on IBS symptoms, in a randomized, double-blind, placebo-controlled clinical trial including patients with diarrhea-predominant IBS (IBS-D). Patients were randomized to receive either B. coagulans GBI-30, 6086 or placebo once a day for 8 weeks. Patients filled out a quality-of-life questionnaire, and self-assessment diaries were provided to record stool count and consistency, symptom severity, and medication consumption. Of the 61 patients enrolled, six did not meet the inclusion criteria and three were lost to follow-up. Of the remaining 52 patients with IBS-D, the average number of bowel movements per day was significantly reduced for patients treated with B. coagulans GBI-30, 6086 when compared to placebo (P = 0.042). Large variability in baseline scores prevented the assessment of severity scores and quality of life. This small pilot study provides evidence that the proprietary B. coagulans GBI-30, 6086 probiotic is safe and effective for reducing daily bowel movements in patients with IBS-D. Copyright 2009 Prous Science, S.A.U. or its licensors. All rights reserved.
PMID: 20140275 [PubMed - in process]
Some of the studies are done by the actual companies just fyi
My website on IBS is www.ibshealth.com