Doctors say that the case of a woman who developed a severe heart rhythm disorder after taking a traditional Chinese medicine serves as a warning that just because a remedy is herbal does not mean that it is not potentially lethal.

The woman living in southern China has been rushed to hospital after collapsing with a racing heartbeat, skin that had turned blue, and a dangerously low blood pressure of 50/30 (normal blood pressure is 120/80).

She had been previously healthy and had no history of heart-rhythm problems.

Doctors diagnosed her with bidirectional ventricular tachycardia, a rare and serious heart rate disorder. Tests showed her blood was positive for aconitine, a toxic substance produced by the Aconitum plant, which is also known as wolfsbane, devil's helmet or monkshood.

The patient's husband reported that the woman had consumed about 50 millilitres of an alternative medicinal liquid about 30 minutes before she collapsed and lost consciousness.

Aconitine is the primary ingredient of a traditional Chinese medicine (TCM) called Fuzi, which is made from the roots of monkshood. It is commonly used by TCM practitioners in southern China to relieve pain and reduce inflammation.

The doctors tried to treat her with two anti-arrhythmia drugs called amiodarone and metoprolol, as well as with lidocaine and potassium chloride; but none of them worked to restore a normal heart rhythm.

Finally, doctors decided to pump the woman’s stomach, using a gastric tube to suction out the contents of her stomach. Two hours later, her BVT ended and her circulation improved.

Writing in the Canadian Journal of Cardiology, lead author Dr. Zhong Yi of the Aerospace Center Hospital in Beijing says the public needs to be warned about the risk of severe poisoning that can accompany the use of Fuzi.

He added that it’s clear that treating aconitine-induced heart rate disorders is difficult, noting that the usual drugs proved ineffective in controlling this woman’s BVT.

Commenting on the report, Dr. P. Timothy Pollak of the Department of Medicine at the University of Calgary, cautioned that "not all products of Mother Nature are free of harm.”

He noted that aconitine is not the only naturally derived substance that can cause potentially deadly heart rhythm disorders.

“The report also demonstrates the human tendency to think that if a little is good, more must be better,” he said in a statement.

Dr. Pollak also advises doctors to discuss TCM and other alternative remedies with their patients.

"Dodging the discussion can only lend credibility to any patient suspicions that as a practitioner of Western medicine, you have been denied the secrets of alternative remedies or are hiding them, for ulterior motives,” he said.