The Issue of Dose in the Use of Chinese Ready-Made Medicines
By Bob Flaws, LAc, FNAAOM (USA), FRCHM (UK)
If you're like me, you get at least one spam e-mail message per day offering Western prescription drugs either at a discount or without a doctor's prescription. If you've ever looked at any of these offers, you know that any given Western prescription medicine, and even many over-the-counter medicines, typically come in a variety of dosages.
For example, the antidepressant amitriptyline (Elavil) comes in 10, 25, 50, 75, 100, and 150 mg tablets. The anti-anxiety medicine alprozolam (Xanax) comes in 0.25, 0.5, 1, and 2 mg tablets. The beta-blocker atenolol (Tenormin) comes in 25, 50 and 100 mg tablets, and levothyroxine (L-Thyroxine) comes in 0.0125; 0.025; 0.037; 0.05; 0.075; 0.088; 0.1; 0.112; 0.125; 0.15; 0.175; 0.2; and 0.3 mg tablets.
This variety of dosages for the same medicine underscores a fact that any Western MD knows: Different patients may need different dosages of the same medicine. While the importance of proper dosage is always taught to Oriental medicine students studying the prescription of bulk medicinals, it is sometimes not discussed in any depth when it comes to the prescription of ready-made (patent) medicines.
In China, ready-made medicines are rarely prescribed by professional medical practitioners. They are primarily meant for over-the-counter use by laypersons, and the treatment of chronic conditions or the consolidation of therapeutic results after more active remedial therapy. Therefore, the stated dosages on the packaging tend to be low to prevent accidental overdose by the untrained. The problem is that here in the West, many if not most professional practitioners do prescribe these kinds of ready-made Chinese medicines for the remedial treatment of active disease. However, in my experience, many of us simply recommend the dosage written on the label. I know that for many years I certainly did. After all, those are the directions, aren't they?
The answer is, yes and no. Yes, if the person is buying the medicine over-the-counter on his or her own volition; no (usually) if we are prescribing the medicine professionally to one of our patients. In that case, as a prescribing practitioner, it is our responsibility to determine exactly what dosage is best for each individual patient. Just as one dose of Western pharmaceuticals does not fit all, so also does a single dose of Chinese medicinals not fit everyone. In fact, the determination of correct dose is one of the things our patients are paying us for, whether they know it or not. So, what are some of the criteria necessary for determining the correct dose of a Chinese ready-made medicine?
There are five things to keep in mind when trying to determine the correct dose for a given patient: age; weight; disease severity; disease diagnosis; and medicinal strength. For instance, babies and young children should be given smaller doses than adults, due in part to their immature metabolisms and medicinal sensitivity. However, the elderly (such as those over 60) should also receive half-doses, due to the decline in function of the digestive system, as well as that of the liver and kidneys. Because the elderly do not metabolize medicines as quickly as younger adults, medicines stay in their systems longer.
The second thing to take into account is a patient's weight or body mass. The larger the patient, the more medicine he or she typically will require to catalyze changes in that mass of cells. A patient who weighs 300 pounds will require significantly more medicine than a patient who weighs 150.
The third factor is disease severity. In Chinese medicine, the more severe or acute a disease is, the higher the doses we usually administer. That is because we are trying to achieve results as quickly as possible, in order to minimize pain and suffering, and the possibility of irreversible damage.
The fourth factor is disease diagnosis. This tells us the natural history of the condition; for instance, whether it is self-limiting, relapsing-remittent, chronic, progressive, disabling, fatal, etc. In acute diseases of expected short duration, we typically prescribe high doses to knock the disease out as quickly as possible, while in chronic, lingering, slowly progressive diseases, we typically prescribe lower doses in a more user-friendly form of administration to assure good patient adherence over a long period of time. For example, in a relapsing-remitting disease such as multiple sclerosis, we may prescribe high-dose decoctions during relapses and low-dose, ready-made medicines during remittent stages.
The fifth factor in determining dosage is somewhat more difficult to deal with. Unless we know how strong a medicine is, how can we determine what its dose should be? Perhaps, since practitioners do not always ask for this information, some herb companies have not figured there is a need or desire for this information. However, if we want to earn the status, respect and earnings of Western MDs, I believe we must truly practice medicine, albeit Chinese medicine, at the same professional level, and one of the things that means is prescribing individualized dosages of medicines to individual patients. Therefore, one of the first questions when considering prescribing a Chinese ready-made medicine to a patient is, "How strong is that medicine?"
Since most Chinese ready-made medicines are made from extracts, one way of answering that question is to know the concentration ratio used in making that medicine. If a medicine is a 5:1 extract, that means that five pounds of bulk herbs were used to make one pound of finished medicine; a 7:1 extract means that seven pounds of bulk herbs were used to make one pound of finished medicine; and a 12:1 extract means that 12 pounds of bulk herbs were used to make one pound of finished medicine. The assumption here is that the higher the concentration ratio, the more potent the medicine is. However, that still does not tell us everything we need to know.
In standard professional Chinese medicine using bulk formulas, the average daily dose of a single medicinal is nine grams. If there are 10 ingredients in a formula, that means a dose of 90 grams per day made into decoction. While we cannot know exactly how that translates to liquid when the patient cooks the bulk formula, we want our patient to receive the equivalent of not less than 90 grams of Chinese medicinals per day for the remedial treatment of active disease.
If we assume those 90 grams of bulk medicinal become 60-70 or more grams of liquid medicine, we would need to prescribe 13-15 grams per day of a 5:1 extract; 10 grams per day of a 7:1 extract; seven grams per day of a 10:1 extract; and only five grams per day of a 15:1 extract. In real life, if a patient is also receiving acupuncture, they might not need as much medicine since, unlike in China, they are being treated by more than one modality. So maybe you could cut the dose down to 45-50 grams per day. In that case, it would only take 10 grams per day of a 5:1 extract; five grams per day of a 10:1 extract; and 3-4 grams per day of a 15:1 extract.
Since, typically, unwanted side-effects are directly proportional to increased dose, in general, as prescribing physicians, we want the lowest dose that will achieve the intended therapeutic effects within the desired time frame. This also means we should start patients with chronic diseases on low doses and then raise them, increment by increment, until one achieves the intended therapeutic effect with either no or the least adverse reactions. Further, when patients are taking Chinese ready-made medicines long-term for chronic diseases, they should be allowed breaks or rests every so often, so that they do not become habituated to the medicine. For instance, every 6-8 weeks, they may be given 5-7 days off to allow their metabolism to reset itself.
In closing, if you're not getting the results you expect from Chinese ready-made medicines, raise the dose and consider using a higher concentration extract.