Homeopathy, a holistic medical system developed two centuries ago by a German physician, is finding increasing global acceptance as an effective healing method though conventional medicine still views it with scepticism.
Samuel Hahnemann (1755-1843) formulated the principles of homeopathy on the idea of "like cures like".
The physician had observed that Peruvian or China bark was prescribed to combat malaria but also caused malaria-like symptoms in healthy people.
Hahnemann then tried out several other plant, animal and mineral substances on volunteers and himself and kept a diary of the symptoms and developed numerous medicines in this way.
"Hahnemann knew 140 medicines. Today there are between 3,000 and 4,000," says Karl-Wilhelm Steuernagel, chairman of the German Association of Homeopathic Doctors (DZVhae) in Bonn.
In his main work "Organon", published in 1810, Hahnemann explained holistic medicine and the cause of illness, which he saw as a dysfunction of the life force in the body.
Classical homeopathy, as developed by him, implies gathering information on all aspects of a patient's physical, emotional and mental state.
The remedy is available in the form of small pellets of liquid developed in potencies and containing miniscule portions of the original substance mixed with water and alcohol.
Preparing the medication includes "forceful shaking" to speed up its effectiveness. The potency is denoted in figures. D1, for instance, means a ratio of one to 10, D2 of one to 100.
From a potency of D24, the homeopathic medicine has been diluted to such an extent that it no longer includes molecules of the original substance. According to Hahnemann, the remedy however includes an "imprint" of the original substance.
"What happens physically is completely unknown," according to Steuernagel.
Numerous tests have proven that homeopathy works. The medication should only be prescribed by a trained homeopath who has examined the patient carefully.
Conventional medicine still rejects homeopathy to a great extent.
"I don't believe in the pellets, especially not in the high potencies as homeopaths have not backed up their claims with scientific evidence so far," says Bruno Mueller-Oerlinghausen, chairman of the German Commission on Medication in Berlin.
"There is no doubt, however, that homeopathic physicians often have enormous success," according to Mueller-Oerlinghausen.
"It is, however, simply a placebo effect."
Biologist and homeopathic critic, Rainer Wolf, of the Biocentre at the University of Wuerzburg, has a similar opinion. "The body to a large extent heals itself. It is treated in some way and it believes in the cure."
But even critics like Mueller-Oerlinghausen concede that homeopaths are often "the better doctors because they take time with their patients".
Sceptics argue that there is much in favour of the placebo argument because homeopathy is very effective in so-called psychosomatic illnesses such as migraine, skin ailments and unspecified stomach pains.
But homeopath Steuernagel rejects such statements, saying that homeopathy can do much more than that. "It is useful for all types of illnesses, acute and chronic," he says.
Trained homeopaths, meanwhile, cover a wide spectrum of diseases including cancer, alcoholism and psychological disorders. Homeopathy is only excluded where cell structures have been destroyed. Diabetes, for instance, cannot be treated by homeopathy, according to Steuernagel.
Most health insurance policies do not cover homeopathic treatment. "Most of my patients settle the bill out of their own pocket," he says.
Steuernagel sees no reason why homeopathy should be sidelined by conventional medicine. "All doctors who offer homeopathy are trained physicians who have completed an additional three-year training course. Only then can they call themselves homeopathy doctors," he says.
The pros and cons of homeopathy are the subject of intense debate in many countries and at the government level. German Health Minister Ulla Schmidt even wrote of a recent German congress on homeopathy, saying it took a "leading role because of its holistic approach".