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Acorus calamus

Acorus calamus is a plant used in traditional medicine. Due to its β-asarone content, it has been deemed unfit for human consumption.

Our evidence-based analysis on acorus calamus features 48 unique references to scientific papers.

Research analysis led by and reviewed by the Examine team.
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Summary of Acorus calamus

Primary information, health benefits, side effects, usage, and other important details

Acorus calamus, commonly known as sweet flag, is a seasoning and herb traditionally used in Ayurveda and traditional Chinese medicine for its cognitive-enhancing properties.

Preclinical studies suggested that Acorus calamus supplementation had potential for treating neuropathic pain.

Unfortunately, supplementation of Acorus calamus is not practical. Studies that last longer than a year show that even very low-dose supplementation can cause organ damage and intestinal tumors. This is because Acorus calamus contains β-asarone, which is toxic and a known carcinogen.

The main mechanism of Acorus calamus involves a potent interaction with GABAA receptors.

The active ingredient in Acorus calamus is β-asarone, which is also responsible for the plant’s main mechanism. Though it is possible to extract and remove β-asarone from the plant in order to make supplementation safe, this process also renders the plant useless.

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How to Take

Recommended dosage, active amounts, other details

Before supplementing Acorus calamus, please review the toxicology information on this page. Acorus calamus is unfit for human consumption because of its β-asarone content. β-asarone is toxic and a known carcinogen.

Some studies have used an ethyl acetate extraction of Acorus calamus, which is supposed to be free of β-asarone. This extraction appears to be effective in the range of 100-200mg per kilogram of bodyweight. This translates to an approximate human dose of:

• 1,100-2,200 mg for a 150lb person

• 1,500-2,900 mg for a 200lb person

• 1,800-3,600 mg for a 250lb person

It is not guaranteed that any extract is completely free of β-asarone. Acorus calamus supplementation is not recommended.

Things to Note

Also Known As

Sweet Flag, Golomi, Ugragandha, Vacha, Vekhanda, Bach, Calamus Oil

Do Not Confuse With

Acorus Gramineus (Japanese or Dwarf Sweet Flag)

Caution Notice

Contains known carcinogens

High toxicity

  • Chronic ingestion (2 years or more) of low dose β-asarone in rats has induced a high prevalence of intestinal tumors and minor but ubiquitous organ damage

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Click here to see all 48 references.