Terms of the Trade 3: Astringent
Don’t worry, we’ll get back to those Alterative differentials I promised sometime in the near future.
For now let’s deal with an often misunderstood herbal action: astringency. In the most physical sense, astringents are those substances that tighten tissues on contact, resulting in that puckery mouth feeling so familiar to anyone who’s ever bitten into a green apple, tasted too strong black tea or chewed on a green banana peel. There’s a tendency to label astringents as herbs that dry the tissues out, but this is an oversimplification. In reality, astringents contract tissue and thus tonify. This can serve to lessen inflammation or irritation, strengthen weakened tissue and therefor provide a stronger barrier against infection, and can provide symptomatic relief from issues resulting from excessive discharge of fluids such as diarrhea, bleeding, vaginal discharge, chronically heavy menstrual periods, profuse sweating or even excessive urination.
And so, astringents help hold fluids within the body, which can be very desirable when they are escaping inappropriately. They also firm the tissue, which is wonderful when the integrity of the skin has been broken and needs to be retightened in order to prevent infection, inflammation and an over abundance of bleeding. They can also be useful in cases of prolapsed organs or in other situations where the tone of the tissue has been compromised and has become weak and/or lax.
Many of our favorite first-aid herbs are astringent, and notable examples include Yarrow, Geranium, Plantain, Raspberry, Mullein, Comfrey, Sage, Elm and Goldenrod. The most useful astringents often have accompanying demulcent properties as in Comfrey, Elm, Violet, Plantain and Mullein. This allows them to effectively soothe the area of injury while also contracting the tissue and clearing inflammation and stopping fluid discharge. This also works very nicely for abraded surfaces within the GI tract, and Plantain is (or should be) highly regarded for its profound effect upon inflammation, pain and dysfunction of the gut. And for those who are chronically dry in nature and exhibit signs such as very dry skin and a withered tongue concurrent with excessive fluid discharge through sweating and urination, then astringents can help to actually hold the moisture in the body rather than drying it out more. And herbs that are both demulcent and astringent can provide the moisture while containing it, which is very useful indeed.
The downside of astringency is that overindulgence in very astringent substances can have several unpleasant side effects, such as decreased digestive function including constipation, and water retention in some cases. Of course, many astringents are also diuretics and alteratives, and so help to self-buffer any negative effects. Side effects are very unlikely to happen with normal use of mild herbs such as Raspberry, and is counterbalanced by the mucilage in gently astringent herbs such as Plantain and Elm. Avoid astringent herbs in cases where there is already a lack of elimination through the waste channels of the body. That is, if you already don’t pee enough, are constipated and/or can’t seem to sweat then don’t chug the Oak bark decoction.