A recent study (CJ Black et al. Gastroenterol 2018; 155: 1753-63) examined the effectiveness of secretagogues for constipation-predominant irritable bowel syndrome (IBS-C). The authors conducted a systematic review and network meta-analysis with 15 eligible randomized controlled trials (8462 patients).
- Linaclotide (290 mcg per day) was ranked first in efficacy using the end point recommended by the FDA for IBS-C trials
- Tenapanor (50 mg twice a day) was ranked first for bloating
- Plecanatide (6 mg per day) ranked first for safety
- Diarrhea was significantly more common with all of the secretagogues except for lubiprostone; nausea was significantly more common with lubiprostone
The authors acknowledge the limitations in comparing medicines without direct head-to-head trials (which may never occur). They state that linaclotide being superior to other treatments had a probability of 88%.
My take: This study indicates that linaclotide may be more likely to be effective than other IBS-C medications; all of these secretagogues have been shown to be superior to placebo.
In this same issue, pgs 1666-9 (J Ruddy), a patient describes her long journey with abdominal pain/GI symptoms. She describes her initial experiences with physicians who were dismissive and not attentive. Ultimately, a physician listened to her and helped her improve after explaining that she had a postinfectious IBS and provided treatment.
Related study: S Ishague et al. BMC Gastroenterol 2018; 18:71. This randomized controlled trial which compared a multistrain probiotic (Bio-Kult, n=181) to placebo (n=179). The probiotic group had a 69% decrease in abdominal pain compared to a 47% decrease in placebo group.