IBS is characterised by abdominal pain and an irregular bowel habit. A wide range of therapies is currently used including fibre supplements, probiotics, antidepressants, hypnotherapy and laxatives.
Fibre, antispasmodics and peppermint oil are used to treat IBS, but evidence of their effectiveness is unclear.
In the new study, researchers sought to determine the efficacy of these alternative treatments.
The research team led by Dr Alex Ford performed a systematic review and meta-analysis of randomised trials comparing fibre, antispasmodics and peppermint oil with placebo or no treatment in more than 2500 adult patients with IBS, reports the British Medical Journal.
Fibre, antispasmodics and peppermint oil were all found to be effective treatments for IBS and none of the treatments had serious adverse effects.
The researchers analysed 12 studies involving 591 patients and compared fibre with placebo, or no treatment.
They found that insoluble fibre such as bran was not beneficial, only isphaghula husk (soluble fibre) significantly reduced symptoms.
The researchers further analysed 22 studies comparing various antispasmodics with placebo in 1778 patients.
The analysis showed that hyoscine, extracted from the cork wood tree, was the most successful at preventing symptoms of IBS.
Peppermint oil seemed to be the most effective treatment of the three, based on four trials involving 392 patients.
All three treatments have been shown to be potentially effective therapies for IBS.