Acorus (shi chang pu)

What is acorus? What is it used for?

Acorus is a grass-like, perennial shrub that resembles an iris. It can grow to a height of approximately seven feet, and is often found in perpetually wet areas, such as the edges of streams, ponds and lakes, and near waterfalls. Just as acorus can reach up to seven feet in height, so can its roots reach up to seven feet in length. Like many plants, the roots of an acorus plant grow horizontally, and spread out just below the surface of the soil. The roots and rhizomes are used in many herbal preparations, and are cut into lengths and dried before being used.

Acorus root has a long history in traditional Chinese medicine. According to the principles of traditional Chinese medicine, acorus root has pungent and warm properties, and is associated with the Heart, Stomach, Liver and Spleen meridians. It is one of the most commonly used Chinese herbs for the treatment of mental disorders, and was listed as a superior herb in the Shennong Bencao Jing. In modern times, it is typically used to treat constipation and lessen swelling, and as a general sedative. Acorus has also been used in ayurvedic medicine to cure fevers and treat asthma and bronchitis.

How much acorus should I take?

The typical dose of acorus root is between 3-9 grams, usually taken as a decoction. It can also be applied externally, with 250-500 mg of an acorus extract applied to hot bath water for an acorus bath.

What forms of acorus are available?

Dried acorus root can be found at some herbal shops and Asian markets. Acorus root can also be ground into a powder and used in pills, capsules and decoctions. It is often sold as part of a larger formula, usually with schizandra and zizyphus.

What can happen if I take too much acorus? Are there any interactions I should be aware of? What precautions should I take?

As of this writing, there are no known side-effects or drug interactions with acorus root. However, it should not be consumed for long periods of time; anecdotal research has shown that use of acorus oils over extended periods of time may produce tumors in mice. As always, make sure to consult with a licensed health care provider before taking acorus or any other herbal remedy or dietary supplement.