Researchers from Cedars-Sinai in Los Angeles have determined that rifaximin and lubiprostone have the least side-effects when it comes to treating irritable bowel syndrome (IBS).
The findings have been generated from a study of more than two dozen large-scale clinical trials, and are to be published online and in print in the American Journal of Medicine.
IBS sufferers incur many troubling symptoms as it is, such as abdominal pain, cramps, excess gas, bloating and visible abdominal distension. There are several drugs available to treat the condition, but most of them are known to have side effects such as nausea, insomnia, palpitations and decreased appetite.
Dr. Mark Pimentel, a lead author of the study and director of Cedars-Sinai's Gastrointestinal Motility Program said: "For the millions of patients who suffer from IBS, effective treatment options have been very scarce."
The researchers evaluated drugs used for both forms of the condition. For the diarrhoea form, they evaluated tricyclic antidepressants, alosetron and rifaximin, and for the constipation forms of IBS, they examined antidepressants known as serotonin reuptake inhibitors and lubiprostone.
The results showed striking differences in the results, which emphasises how varied treatments can be. They found that for every 2.3 patients who benefited from tricyclic antidepressants, one suffered harmful side effects and had to stop taking the medication. Alosetron was 2.6 patients to every one that had to stop taking the medication, but for rifaximin, this number increased to every 846 patients, one had to discontinue the medication.
Lubiprostone and serotonin reuptake inhibitors were found to have absolutely no 'harm' to IBS patients with constipation, as defined by the study.
Dr Primentel said: "This underscores the need for us to continue to monitor new therapies for this disease.
"While it is important to see benefit with drugs, harm is something we do not often assess well."