Sweet Flag

Last Updated: September 28 2022

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

Sweet Flag is most often used for


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.

What else is Sweet Flag known as?
Note that Sweet Flag is also known as:
  • Sweet Flag
  • Golomi
  • Ugragandha
  • Vacha
  • Vekhanda
  • Bach
  • Calamus Oil
  • Acorus Calamus
Sweet Flag should not be confused with:
  • Acorus Gramineus (Japanese or Dwarf Sweet Flag)
Dosage information

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.

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35.^Si MM, Lou JS, Zhou CX, Shen JN, Wu HH, Yang B, He QJ, Wu HSInsulin releasing and alpha-glucosidase inhibitory activity of ethyl acetate fraction of Acorus calamus in vitro and in vivoJ Ethnopharmacol.(2010 Mar 2)
36.^Wu HS, Zhu DF, Zhou CX, Feng CR, Lou YJ, Yang B, He QJInsulin sensitizing activity of ethyl acetate fraction of Acorus calamus L. in vitro and in vivoJ Ethnopharmacol.(2009 Jun 22)
38.^Lee SH, Kim KY, Ryu SY, Yoon Y, Hahm DH, Kang SA, Cho SH, Lim JS, Moon EY, Yoon SR, Lee HG, Yoon DY, Yang YAsarone inhibits adipogenesis and stimulates lipolysis in 3T3-L1 adipocytesCell Mol Biol (Noisy-le-grand).(2010 Jan 24)
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