Contra-indications of Desert Sage

As mentioned previously, there is little current research on the effects of Artemisia tridentata on the human body. Michael Moore comments on his website that American herbs are not as “sexy” as herbs from, say, the Amazon, and so they are widely ignored. (33) Much of the research that has been done is dealing with the effects of desert sage on browsing mammals. However, a few cautions are available on the use of desert sage for humans.

Michael Moore states that sagebrush alters liver drug metabolism. In other words, taking desert sage concurrently with an allopathic drug may give unexpected side effects. He also points out that Artimisia tridentata is inappropriate to take during pregnancy, as it is a uterine vasodilator. Additionally, it should not be used while nursing, as it may be present in the milk. The herb may be relatively harmless, but he states that “considering the highly reactive state of pregnancy and the fact that fetal growth is a template that can manifest pharmacokinetics very differently than for an adult”, this herb is mentioned in his list of herbs to avoid during pregnancy and breast-feeding. (34)

A further caution is that “sagebrushes contain both sesqueterpene lactones and essential oils or monoterpenes that are potentially toxic to animals. Big sagebrush has been suspected of being toxic to sheep. It has also been associated with abortions in sheep. However, most of the many species of Artemisia are useful forage plants for range livestock.” (35) This information would seem to support Moore's assertion that desert sage should not be used in pregnancy.

Foster and Hobbs warn that desert sage is of unknown safety, and that it may cause dermatitis in sensitive individuals. (36)

Desert sage contains thujone. It is a narcotic poison that , with high doses over a period of years can cause mental deterioration. “It is best known as a component of the drink absinthe, and it is a component of natural oil of wormwood. Although it was believed to be the cause of absinthism, an alleged syndrome which caused epileptic fits and hallucinations in chronic absinthe drinkers, this has since been questioned.

“In the United States, food or beverages that contain Artemisia species, white cedar, oak moss, tansy or yarrow must be thujone free. Other herbs that contain thujone have no restrictions. For example, sage and sage oil (which can be 50% + thujone) are on the FDA's list of Substances Generally Recognized as Safe.” (37)

Since thujone is insoluble in water, it would be prudent to use desert sage externally, or in infusion or “sun tea” form.

Desert Sage also contains tannins. Chung, Wong, Wei, Huang and Lin report “Tannins (commonly referred to as tannic acid) are water-soluble polyphenols that are present in many plant foods. They have been reported to be responsible for decreases in feed intake, growth rate, feed efficiency, net metabolizable energy, and protein digestibility in experimental animals. Therefore, foods rich in tannins are considered to be of low nutritional value. However, recent findings indicate that the major effect of tannins was not due to their inhibition on food consumption or digestion but rather the decreased efficiency in converting the absorbed nutrients to new body substances. Incidences of certain cancers, such as esophageal cancer, have been reported to be related to consumption of tannins-rich foods such as betel nuts and herbal teas, suggesting that tannins might be carcinogenic. However, other reports indicated that the carcinogenic activity of tannins might be related to components associated with tannins rather than tannins themselves. Interestingly, many reports indicated negative association between tea consumption and incidences of cancers. Tea polyphenols and many tannin components were suggested to be anticarcinogenic. Many tannin molecules have also been shown to reduce the mutagenic activity of a number of mutagens. Many carcinogens and/or mutagens produce oxygen-free radicals for interaction with cellular macromolecules. The anticarcinogenic and antimutagenic potentials of tannins may be related to their antioxidative property, which is important in protecting cellular oxidative damage including lipid peroxidation. The generation of superoxide radicals was reported to be inhibited by tannins and related compounds.” (38) Clearly, the jury is still out as to whether tannins in desert sage are contraindicated for human usage or not.