A calendula cream may reduce dermatitis after radiotherapy
Some homeopathic medicines may ease the side-effects of cancer treatments without interfering in how they work, a scientific review has concluded.
The Cochrane Collaboration said, while there were few studies, it did appear that some effects of radiotherapy and chemotherapy could be alleviated.
It highlighted in particular calendula to prevent dermatitis, and what is known as Traummel S for mouth sores.
But it said further work was needed to confirm these findings.
Eight studies with a total of 664 participants were considered by the group, led by Dr Sosie Kassab, a specialist in complementary cancer therapies at the Royal London Homeopathic Hospital.
Three studies looked at preparations to counter the skin reactions of radiotherapy, but only one was deemed to be high quality.
This, from France, suggested that calendula - from marigolds - reduced acute dermatitis in breast cancer patients more effectively than the more conventional treatment trolamine. It involved 254 patients.
One of three studies on treating the side-effects of chemotherapy was deemed high quality.
This found that Traumeel S, a mixture which includes belladonna, arnica, St John's wort and echinacea, was effective in reducing stomatisis - painful mouth sores - when used as a mouthwash.
Two other studies of homeopathic treatments on menopausal symptoms brought on by cancer treatments were declared to be of high quality but did not provide any evidence that the treatments worked.
There was no evidence to show that any of these treatments interfered with cancer therapies, and indeed one study showed that radiotherapy was less frequently interrupted in the group receiving homeopathic care.
But the Cochrane team acknowledged: "The review found few studies, and most were small."
Edzard Ernst, professor of complementary medicine at the Peninsula Medical School, said there were "several problems with the body of evidence examined by this review.
"First, independent replications are lacking completely but would be necessary before we can accept any of these treatments in routine healthcare.
"Second, nobody doubts that undiluted remedies can have effects; and interestingly, the positive studies here seem to be on such medicines rather than on the highly diluted treatments which are a hallmark of homeopathy.
"In fact, the calendula cream found to be effective in one study is not diluted at all and thus it cannot, to all intents and purposes, be considered to be a typical homeopathic remedy.
"Finally, this review found hardly any high quality studies in the first place. So overall, this new piece of evidence simply confirms plenty of previous research demonstrating the unproven nature of homeopathy."