Saturday 24 January 2015

Liquid Joy

This post was originally going to be about giving up things you're addicted to by tapering doses.  Say you drink four cups of coffee a day and you aim to reduce that to one.  You start by drinking three instead of four a day, which is a 25% reduction, but if you then cut it by one again, that's a reduction of 33 1/3%, so it gets more and more severe, and whereas that may be fine with coffee, with other drugs it could be dangerous, so instead of that you do something like have three cups over a thirty hour period.

Then I realised that the example was silly because this:


is a liquid.  It's not like you're taking Pro Plus tablets and are going to end up shaving bits off them so you can carry on going down by a quarter, because fluids are practically speaking infinitely divisible in quantities of that size.  That's about three hundred millilitres of coffee in that picture.  If you want to reduce that by a quarter, you just drink 225 ml instead, assuming the strength is the same.

This illustrates one of the many advantages liquid medicines have over solid preparations, and to this extent this post isn't really about herbs at all so much as how drugs are delivered.  In a sense, they aren't drugs at all because the word "drug" means "dry", which is what liquids aren't.

Peruse the following pic if you will:


All of these are herbal preparations.  Many people, such as me once before I started training, imagined herbal remedies were normally in the form in the mortar at top left.  These are dried stinging nettle leaves. I always used to imagine that herbal remedies were usually in the form of teas, the herbs being dried and steeped in hot water for twenty minutes or so, strained and drunk.  Sometimes they are, of course.  Chamomile is probably best delivered this way and diuretics such as nettle leaves are also appropriately taken with water, so that makes sense.  Back in the day, a ridiculously large number of herbs were considered to be diuretics due to the simple fact that they were drunk as teas, in water, so technically they almost all were, but because of the water rather than the plants.  Water is of course a liquid, so it does mean that the dose can be adjusted very precisely.  Three hundred millilitres of nettle tea can be adjusted easily to well under 0.1% of the dose, which is so precise as to be completely unnecessary.

It does sometimes make sense to take simples - single herbs - in this way.  However, herbal prescriptions usually involve several remedies together, and if fairly large plant organs are involved, problems can emerge.  Chamomile flower heads, cinnamon cambium and ginger rhizomes, to give three examples, might need to be mixed together.  The chamomile is springy and light, so it will tend to rise to the top.  Ginger rhizomes are lumpier and denser, so they will sink.  Cinnamon cambium (the layer under the bark) will also tend to float but will also be in long quills.  This means that in that form, a bag of the three herbs given for whatever reason will tend to be uneven.  The patient is likely to get wildly different doses at different times.  Not is pulverisation the answer because this exposes the herbs to oxidation, light and fungal spores.

Therefore, for a Western herbalist the usual preference for most herbs is in the form at bottom left - tincture, in this case of Trifolium pratense.  This is the herbal remedy infused in a solvent of some kind, such as ethyl alcohol and water, polyethylene glycol, glycerol, diethyl ether or vinegar, for about a month, pressed and often mixed with other herbs, then taken in recently boiled water to drive off the solvent.  These can sometimes be incompatible or render each other ineffective, and so forth. I could go on and on at this point because there's a lot to this, but I won't.  Nevertheless they have a number of advantages over capsules and tablets, two of which currently spring to mind.  The first is that because they can be mixed, the patient can take a dose of every drug prescribed at once, meaning that concordance is greater.  Concordance is the degree to which a patient follows the advice given, also known as compliance and adherence, and is a hugely important factor in medicine which is frustratingly often ignored.  The other is that as mentioned above, the dose can be very precisely adjusted - dare I say "titrated"? - to an extent way beyond the degree to which tablets can be.  In fact this needn't even apply to herbs.  The same would apply to any medicine which can be taken in liquid form.  It's also easier to reduce the dose of a liquid gradually.  Actual tinctures themselves bring problems of their own, but titration and to a lesser extent concordance ain't two.  For some reason, liquid remedies in the dominant form of Western medicine are in the minority, usually given to particular sections of the population such as children, and, probably due to economies of scale, many times more expensive per dose than pills.  This is a great pity.

Wonderful though liquid solutions are, they're not always ideal.  This is illustrated in this picture by the jar of cream.  You don't usually expect to paint a tincture onto the skin and if you did that on its own, it wouldn't be very effective.  Instead, you may put it in a cream.  Creams are emulsions, that is, suspensions of oil in water or water in oil maintained by an emulsifier, which could in fact be a herb such as licorice or marigold if that's needed.  They are also intimidatingly hard to make, but a tiny ray of hope is offered by the phrase in the British Pharmacopoeia, "some creams have only a creamy appearance".  They block the evaporation of water from the skin, hydrating it and making it easier for the drugs in them to get into the body by enabling them to dissolve into and pass into the body fluids.

There are two other definite liquids in that picture.  Tea tree oil is at the top right.  Essential oils are usually liquids, with the exception of menthol and another one I've forgotten which is also, I seem to remember, explosive.  Essential oils are a whole subject in themselves so I don't want to go into them here except to say that the way I use them is rather unlike the way an aromatherapist would.

Finally, there are certain herbs which can't or shouldn't be made into tinctures because their physical properties either prevent that or are useful in themeselves.  That mug contains the legendary "gloop" which annoys Sarada so much.  It's fenugreek in infusion form and it's slimy and nasty because it's high in mucilage.  Mucilaginous herbs often have uses in addition to their gloopiness, but the gloopiness often provides a protective layer or soothes the surface it's applied to.  I of course am taking fenugreek because it's phytoestrogenic.

I've skimmed over the non-tincture elements of that picture on the whole, but you can probably see from this that when the option exists, drugs of any kind are probably best given in liquid form, and that was basically what I wanted to say today.  Bye for now!

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