Katherine Bibeau was willing to try any treatment that would slow her decline from multiple sclerosis (MS) and keep her out of a wheelchair. In March 2004, after hearing about a “longevity physician” who offered a revolutionary therapy for people with MS and other illnesses, the mother of two from Minnesota travelled to West Columbia in South Carolina to find out more.

At his Health Dimensions Clinic, Dr James Shortt arranged to give the 53-year-old medical technician an infusion of a chemical that he touted as a cutting-edge alternative treatment. It was something dirt cheap and readily available that many of us might find somewhere in our bathrooms: hydrogen peroxide, which is often used as hair dye or mouthwash, and as an antiseptic.

After the first of three planned injections, the doctor’s records report that Bibeau complained of “nausea”, “leg pain” and later “bruises”, with no clear cause. Within days she had died.

In America, the legal investigation into Dr Shortt’s practices made national headlines. Last year Bibeau’s husband David told CBS News how “she went Tuesday, she went Thursday. And by 11 o’clock on Sunday she died,” adding that Shortt never told him or his wife about any serious risks.

A post-mortem report by the pathologist Clay Nichols revealed that Bibeau suffered “systemic shock” and “DIC” — a disorder in which the blood loses its ability to clot. Certainly, Nichols concluded, “this unfortunate woman died as direct result of infusion of hydrogen peroxide”, which is known to destroy blood platelets — the cells that coagulate to stop bleeding — and put oxygen into the bloodstream, where it can form bubbles and stop blood flow to vital organs.

Because it was “a deliberate act to put unapproved drugs into her veins”, Nichols ruled Bibeau’s death a homicide. Dr Shortt’s medical licence was withdrawn in 2005 and revoked this year. In reviewing the case, Nichols claimed to be “pretty well flabbergasted that somebody would administer this type of therapy intravenously. I’d never heard of it before”.

Yet Bibeau was by no means the first person to undergo intravenous hydrogen peroxide (or H202) treatment, also called oxidative therapy, and Dr Shortt is not the only doctor to administer it. It does not require an extensive search of the internet to find other alternative therapists offering injections of 3 per cent strength H2O2, the concentration used in over-the-counter preparations to clean and disinfect minor cuts and wounds, and which was once used in products to clean sinks and baths.

Nichols says that there is no proven use for such a practice: “It’s not the cure for any disease. It’s not the treatment for any disease. It’s a bogus treatment.”

Yet there are also websites that offer 35 per cent “food grade” hydrogen peroxide — ten times more powerful, and strong enough to bleach fabric and decontaminate waste water, yet designed to be diluted and drunk.

Such is the popularity and growing misuse of this chemical that the American Food and Drug Administration (FDA) recently issued a warning against it, saying that it had never approved high-strength hydrogen peroxide to be taken internally and considered it a highly dangerous procedure, even if it was handled according to the manufacturer’s directions.

Dr Steven Galson, director of the FDA’s Centre for Drug Evaluation and Research, says: “No one has presented any evidence that hydrogen peroxide taken internally has any medical value. In fact, consuming it in the manner touted by these websites could lead to tragic results.”

Hydrogen peroxide, says the FDA, is highly corrosive and could damage the nose, throat and lungs. It is capable of causing irreversible harm to the eyes, including blindness, and could kill.

A 1994 study published in the Journal of Clinical Toxicology reported that seven children had died from accidentally ingesting 35 per cent hydrogen peroxide — the strength sold by some health shops and online.