It may sound like the most unappealing treatment available, but a European study has concluded that inserting fecal material from a healthy person into the gut of somebody with severe diarrhoea may cure their problem better than antibiotics.

The study, which appeared in the New England Journal of Medicine, involved patients who had repeated bouts of diarrhea caused by a bacterium known as Clostridium difficile, which can take over the intestines after antibiotic treatment has killed off the beneficial bacteria found in the gut.

About 3 million people in the United States are infected annually with the bacterium, known as C. diff, which spreads mainly through hospitals, nursing homes and doctors’ offices.

When it controls the gut, it can be hard to eradicate.

Antibiotics typically only work in 15 to 26% of patients with C. Diff, and after repeated rounds of treatment, the drugs become less effective.

“The efficacy of antibiotic therapy decreases with subsequent recurrences, and it seems reasonable to initiate treatment with donor-feces infusion after the second or third relapse,” wrote researchers led by Josbert Keller of the University of Amsterdam.

Keller and his colleagues compared three treatments in a small trial.

Thirteen volunteers with C. Diff received a standard antibiotic four times a day for 14 days. After 10 weeks, four were free of bacteria-related diarrhoea.

Another 13 patients had the same drug therapy after drinking a solution to clean out the bowel, known as bowel lavage. That worked in three cases.

The remaining 16 volunteers, had a brief treatment with the antibiotic, combined with bowel lavage, followed by the infusion of 500 millilitres of diluted donor feces through a tube that went into the nose, down the throat and into the small intestine.

In the three cases where the treatment failed, the doctors re-treated patients with fecal material from a different donor.

That worked in all but one case.

Among the volunteers in the non-transplant groups who had a relapse, 18 were later given a fecal transplant. It cured 15 of them, although four of the 15 needed two treatments.

“I’ve done 90 of these now in the last four and a half years,” said Colleen Kelly of Brown University’s Alpert Medical School, who was not connected with the study but uses fecal transplant in her practise.

“In patient after patient who has failed multiple courses of antibiotic, if you give them a dose of stool, they get better.”

When side effects were tallied in the transplant group, 94% of patients reported diarrhea, 31% had cramping and 19% had belching, but all of those disappeared within three hours. Nineteen% ultimately reported constipation after treatment.

Feces transplants may sound extremely distasteful, but the patients were desperate, Keller said.

“There was nothing else they could do. There was no psychological hurdle for them,” he said.