Alternative medicines potentially unsafe: Expert

London - You should go slow if you depend too much on alternative medicines as there is no way of knowing whether they are really safe, suggests a leading expert.

Edzard Ernst, professor of complementary medicine at Peninsula Medical School in Exeter, UK, says trials into treatments such as chiropractic manipulation, acupuncture and herbal remedies too often fail to record incidents when patients suffer adverse effects.

According to Ernst, the main chiropractic treatment technique involves manual therapy, including manipulation of the spine, other joints, and soft tissues; treatment also includes exercises and health and lifestyle counselling.

While Ernst's research indicated there were conditions for which alternative medicine could be useful, he believed in most cases people should avoid going in for it. Chiropractic manipulation could even be "lethal", said Ernst, the Telegraph reports.

"Most people believe that alternative treatments are safe. But how sure are we that this is true," he asked. "My team conducted several investigations which revealed that, in clinical trials of alternative medicine, adverse effects tend not to be mentioned.

"Alternative medicine researchers are often enthusiastic amateurs who think that research is for the purpose of promoting their treatment, rather than testing hypotheses," said Ernst.

He and a colleague have just concluded a study, looking at reporting of adverse effects in trials of chiropractic treatment. This involves manipulation of the spine to alleviate a range of problems, according to the Journal of the New Zealand Medical Association.

Of the 60 randomised controlled trials published between 2000 and 2011, "29 failed to mention adverse effects," he said. "Previous research had demonstrated that 50 percent of patients experience adverse effects after chiropractic treatment and some can be severe, even fatal," he claimed.

Ernst has carried out similar reviews of trials into acupuncture and herbal remedies and found the degree of lack of reporting of adverse effects to be "fairly consistent." This omission had "important consequences," he said.

"Not only does it violate basic rules of publication ethics, it also means that, due to under-reporting, our knowledge of adverse effects of alternative medicine is incomplete and not reliable. If investigators fail to report, we will not know," Ernst concluded.