Essiac is an herbal remedy that has become a well-known alternative treatment for several medical conditions, including cancer, general inflammation, sinusitis, bacterial/viral/fungal infections, and more. Its roots lie in traditional native medicine, but it has grown into a commercially available, widely distributed product in the past 100 years.

Origins and Development

It was originally formulated by a Canadian Ojibwa healer an uncertain number of years ago, with the purpose of purifying the body and restoring/maintaining balance between body and spirit; it was not until the 1920’s, though, that its use became widespread.

In 1922, Canadian nurse Rene Caisse learned of the four-herb mixture from a patient who claimed that use of the native medicine cured her breast cancer. Between that time and her death in 1978, Caisse dedicated her life to using essiac to treat cancer, even treating her own aunt and mother with reported success. Because of the tremendous role that Rene Caisse played in researching and promoting the use of this mixture, it became called “Essiac,” which is Caisse spelled backward.

Throughout the 1930s, Caisse ran a free cancer clinic in Ontario, focused on treating patients with Essiac. However, she closed the clinic in the early 1940s shortly after the Royal Cancer Commission of Canada did not find evidence to convince them of Essiac’s efficacy in cancer. Despite the clinic’s closure, Caisse continued to treat cancer patients with Essiac due to widespread support from the public. At the same time, she also pursued further research to support use of the mixture.

In the last years of her life, Caisse gave the Essiac formula to a Canadian company because the company had received government permission to conduct clinical experiments testing Essiac’s efficacy in active cancer patients. During the four years that this company researched Essiac, results remained inconclusive. Neither the U.S. nor Canadian government allowed Essiac to be approved as a medical treatment; as a result, Essiac has been sold as a nutritional supplement since the 1980’s. And though it was denied the status of a federally approved drug, Essiac and Essiac-like products have continued to gain popularity, particularly in North America.


While it is generally accepted that Caisse’s original formula was made up of the four ingredients previously mentioned (burdock, sheep sorrel, slippery elm, and turkey rhubarb), Caisse never actually published her recipe for Essiac, due to fear of exploitation. Furthermore, Caisse also experimented with different combinations and concentrations of herbs in order to further improve and perfect the mixture. Namely, between 1959 and 1978, Caisse worked with a well-respected American physician, Dr. Charles Brusch, to improve the recipe.

The results of Caisse and Brusch’s clinical and laboratory experiments led to the incorporation of four additional herbs to the recipe: watercress, red clover, kelp and blessed thistle (now marketed as Flor Essence). These additions were made to strengthen the formula’s synergistic effects, improve taste, and also render the mixture pharmacologically available solely by oral administration, whereas they previously injected sheep sorrel into patients’ muscles. These changes and lack of recipe publication unfortunately mean that the true formula as used by Caisse is uncertain. Furthermore, the formula she used was not even the true original, as she strayed from the original Ojibwa recipe during her research.

As Essiac becomes more and more popular, many manufacturers have taken liberties with the mixture’s formula, making it into anywhere from a four- to eight-ingredient recipe.
On top of this, Essiac is currently marketed as a health supplement, and is thus not regulated by the U.S. Food and Drug Administration. This contributes to the lack of conformity among different manufacturers’ Essiac compositions, meaning that different companies and even different batches from the same company can have different ingredients or concentrations of ingredients.

Essiac has a long history rooted in native Canadian medicine and forged through the tireless work of Rene Caisse. Though many details of Essiac remain uncertain, such as the original Ojibwa formulation, the fact remains that Essiac continues to be a popular treatment in the world of alternative and complementary medicine.