Background and aims: Few effective treatment options exist for patients with irritable bowel syndrome (IBS), and many patients state the use of aloe vera products reduce their symptoms. The aim of this pilot study was to investigate the effect of Aloe barbadensis Mill. Extract (AVH200®) in adult patients with IBS in a randomized, double-blind, placebo controlled study.
Methods: Sixty-eight adult patients diagnosed with IBS according to the Rome III criteria were randomized to receive AVH200® or matching placebo for four weeks. Symptom questionnaires were completed on a weekly basis and the patients were asked if they had had adequate relief of their gastrointestinal symptoms.
Results: A tendency towards a higher proportion of responders in the aloe vera group (55%) vs. placebo (31%), (p=0.09) was observed, and the proportion of subjects who reported adequate relief at least 50% of the weeks during the treatment period tended to be larger in the aloe vera vs. placebo group (33% vs. 14%; p=0.12). The overall severity of the gastrointestinal symptoms was reduced in the aloe vera group (314+/-83 vs. 257+/-107; p=0.003) but not the placebo group (276+/-88 vs. 253+/-100; NS), without difference between the groups (p=0.10). AVH200® was well tolerated and no serious adverse events were observed.
Conclusion: Even though the primary endpoint was not met, AVH200® seems to be a promising treatment option for patients with IBS owing to the positive results seen within the secondary endpoints. This study may have been underpowered to detect a clinically meaningful difference between the treatment groups, and therefore larger randomized, controlled studies are required to confirm these results and to elucidate potential mechanisms explaining its effect.