ORIGIN mid 18th cent.: from Latin demulcent– ‘stroking caressingly,’
Demulcents are herbs that contain noticeable amounts of a carbohydrate (a polysaccharide, actually) called mucilage that moistens, cools heat, lessens inflammation and often stimulates local immune response. It was once thought that demulcents could only effect the surfaces they came in contact with, but it is now known that, through whatever mechanism, they are able to systemically moisten the whole body, some people call this the indirect demulcent effect. This means they can provide much needed moisture to places like the lungs where the physical matter of the herb will not touch during ingestion or digestion.
Demulcents are one of the easiest herbal actions to recognize. In fact, you can perceive their actions with just your fingers even by crushing the herb and moistening it. If it becomes gooey and slippery and forms a slimy rope when you pull the pieces of plant matter apart, you have yourself a demulcent. Some herbs are only slightly moistening and it may be harder to detect the mucilage with your fingers (though you should still feel a distinct slipperiness) and it may be easier to make a small amount of tea and feel it on your tongue. This gooeyness is very healing to abraded, inflamed tissue and tremendously valuable wherever there is excess dryness and heat, even (or especially) in constitutional imbalance.
Used externally, these herbs are usually called emollients. I don’t see any sense in confusing people with more terminology than is necessary so I stick to just demulcents in the my writing. The indications are simple and straightforward in most cases, we’re looking for dryness, inflammation and often (but not always) symptoms of excess heat, sometimes accompanied by irritation that won’t heal (usually from lack of adequate fluids). When there’s dryness with obvious heat, Mallow is a great choice. When there’s dryness with some coldness or systemic weakness, Elm is often better for it is more neutral in temperature. If you need something that’s both astringent and moistening, Plantain and Evening Primrose are both exceptionally healing with a very useful balance of astringent and mucilaginous qualities. Most demulcents tend to have marked action on the kidney and urinary tract, with some such as Mallow, being active diuretics. They are very soothing to inflamed or irritated tissues, and can be very useful in the treatment of UTIs, interstitial cystitis, scalding urine and other similar issues as long as the root issue causing the inflammation or infection is dealt with as well.
The polysaccharides tend to precipitate out in alcohol, creating a strange ropey mess in the tincture that renders the mucilage unusable. However, a very low percentage alcohol, just enough to preserve the tincture (say, 20%, 1:5 with dried plant matter), can work ok, it doesn’t have all of the mucilage to be sure (that starts to precipitate out at about 5% or 10%) but it’s still slippery. However, you may not properly extract other useful constituents from the herb such as volatile oils or alkaloids with such a low percentage of alcohol. For this reason, I rarely tincture highly mucilaginous herbs, although I make an exception for Mallow, because the tincture is a quick and very useful treatment for many cases of sore throat, especially when combined with a soothing astringent like Wild Rose. I also make very soothing salves with oil or lard infused with Mallow, Elm or Comfrey. I tend to use water based preparations to work with demulcents and often find them to be the most effective. Fresh plant poultices are also very doable, and a chewed up strip of fresh Elm bark is a wonderful remedy for a great many afflictions, from sore throat to abraded skin. Another excellent way to work with demulcents is in honey, either as an infused honey or even better, with whole freshly dried plant ground up very finely and combined with honey. This is a great to ingest the whole plant in a well preserved, good tasting vehicle. It does vary from plant to plant and situation to situation which form of preparation is most ideal.
Keep in mind that these are plants for dryness, and they will be less helpful (possibly even counterproductive) in cases where there is excess moisture, boggy tissues and copious chronic mucus. Also, cooling demulcents tend to have a very cooling effect on the constitution so be sure to use a neutral to warming demulcent where there is feelings of coldness, pale purulent wounds that refuse to heal or other symptom of coldness.
Cool to Cold Demulcents
Licorice (The Chinese spp is more warming and the American spp more cooling)
Notably Astringent Demulcents