Evidence supporting the use of: Sweet flag
For the health condition: Congestion (lymphatic)
Synopsis
Source of validity: Traditional
Rating (out of 5): 2
Sweet flag (Acorus calamus) has a long history of use in traditional medicine systems, such as Ayurveda and Traditional Chinese Medicine (TCM). In these systems, sweet flag rhizome is valued for its aromatic, warming, and stimulating properties. It is often used to help “clear obstructions” or “move stagnation,” which can include references to lymphatic congestion, although such terminology is a modern interpretation of traditional concepts. Ayurvedic practitioners have employed sweet flag to address issues related to poor circulation, fluid retention, and general sluggishness in the body, which may correspond to lymphatic congestion. In folk herbalism, sweet flag is sometimes included in formulations intended to “stimulate lymphatic flow,” though this use is less well-documented and largely based on practitioner experience rather than codified tradition.
Scientific evidence directly supporting sweet flag’s effect on the lymphatic system is lacking. Most modern research on sweet flag has focused on its neuroprotective, antimicrobial, and digestive properties rather than its impact on lymphatic circulation. No clinical trials or robust animal studies specifically validate its use for lymphatic congestion. Thus, the rationale for using sweet flag for lymphatic congestion is primarily rooted in traditional energetics and historical application, rather than scientific validation. Caution is also warranted due to the presence of β-asarone, a compound in some sweet flag varieties, which has shown toxicity in animal studies.
Other health conditions supported by sweet flag
Abdominal PainAcid Indigestion
Addictions (general remedies for)
Anxiety
Appetite (deficient)
Asthma
Backache
Belching
Bronchitis
Burning Feet or Hands
Burns and Scalds
Colds (decongestant)
Colds (general)
Colds (prevention)
Colds (with fever)
Congestion
Congestion (bronchial)
Congestion (lungs)
Congestion (lymphatic)
Congestion (sinus)
Constipation (adults)
Constipation (children)
Cough (dry)
Cough (general)
Cough (spastic)
Cuts
Diarrhea
Digestion (poor)
Dizziness
Ear Infection or Earache
Edema
Emotional Sensitivity
Energy (lack of)
Fever
Gas and Bloating
Gastritis
Gingivitis
Glands (swollen lymph)