Calamus (Acorus calamus)
Calamus (sweet flag) is a marsh plant whose rhizome has a strong aromatic, bitter profile. Folk traditions describe its use for digestive support and as an aromatic ingredient in herbal preparations. Modern safety considerations are important for this herb.
What it is
Calamus (Acorus calamus) is a perennial wetland plant that grows along the edges of streams, rivers, lakes, and marshes. The traditionally used part is the rhizome.
Traditional uses
Folk traditions describe calamus rhizome as an aromatic bitter used to support appetite and digestion. It is also described in traditional sources for external use such as rinses and baths.
Traditional preparations (educational)
External infusion: A strained infusion has been used historically for rinsing and washing (for example, as a mouth rinse or for skin cleansing).
Hair/scalp rinse (traditional): Some folk preparations combine calamus with burdock root as a long-steeped rinse.
Modern context
Because safety and regulatory status can vary by region and by calamus chemotype, treat this herb with extra caution. If you are considering internal use, consult a qualified clinician and choose products that meet local safety standards.
Safety and precautions
- Do not use during pregnancy or breastfeeding.
- Consult a clinician before any internal use—regulatory guidance and safety concerns exist for calamus in some regions.
- Avoid use if you have low blood pressure or take blood-pressure medications unless advised by a clinician.
- Stop use if you experience adverse effects and seek medical advice.
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Disclaimer: This page is for educational purposes only and does not provide medical advice. Herbs can interact with medications and may not be appropriate for everyone. If you are pregnant, breastfeeding, have a medical condition, or take prescription medicines, consult a licensed clinician before using any herbal product.