Xiang Ru (Mosla): Summer Cold, Damp and Edema

Name

Xiang Ru (mosla, Herba Moslae), recorded in the Mingyi Bielu.

Source and quality

Plant

The aerial parts of Mosla chinensis Maxim., including the cultivated form often sold as Jiang Xiang Ru, family Lamiaceae.

Where it is grown

A well-known producing area is Yifeng County, Jiangxi, with large output and a reputation for quality.

Harvest

Cut when stems and leaves are at their full growth.

Smell and taste

Strongly aromatic; cooling and slightly acrid.

Better grade

Dense fragrance; fine branches with many flower spikes.

Processing

Sliced; used unprocessed.

Nature and action

Acrid, slightly warm; enters lung, spleen, stomach and gallbladder. Disperses wind-cold; transforms damp and harmonizes the middle; promotes urination to ease edema.

When it is used

Wind-cold on the exterior with damp in the middle

Xiang Ru can sweat a wind-cold exterior and also move damp in the spleen and stomach. The picture is chills, fever, heavy head and body, no sweat, epigastric fullness, poor appetite, a greasy tongue coating, sometimes nausea or diarrhea. It is often combined with Hou Po and Bian Dou (Xiang Ru San). That pattern is common after iced drinks in hot weather, which is why older physicians called Xiang Ru “the exterior herb of summer.” For a plain wind-cold it can sit with other cold-dispersing herbs; for middle damp, Cang Zhu or Huo Xiang may be added.

Edema with an exterior pattern

It can sweat damp from the surface and also spread lung qi to open the waterways, so it is used for edema that still has exterior signs — alone in simple cases, or with other water-moving herbs.

Dose

Decoction 6–15 g. To induce a sweat, keep the dose moderate; avoid a huge dose boiled for a long time, and drink it warm. For edema, a denser decoction is the traditional way to move water.