The HPCUS is well aware that homeopathic attenuations are made in a wide variety of settings, from medium scale pharmaceutical companies to compounding pharmacies, from laboratory scale intermediates to extemporaneous preparations in health care practitioners' office. What degree of accuracy is required for preparing attenuations in all these settings? Is one 'rule' appropriate for all?
The two critical steps in preparing each homeopathic attenuation step are ‘dilution’ and ‘succussion’. The Guidelines for Manufacturing Homeopathic Medicines (GMHM) contains a set of guidelines for the procession of succussion. However, the GMHM is silent on the question of precision in measuring the two components. For instance, the GMHM specifies that attenuations are prepared in the ratio of 1 in 10 “parts”. The HPCUS Council on Pharmacy specifically did not employ language using specific measurement units, such as “... 1 ml [1.0 ml or 1.00 ml] of medicinal raw material in a total of 10 ml [10.0 ml or 10.00 ml] of finished first decimal attenuation...”
To have used specific measurement units could have caused two unintended consequences:
a. A misunderstanding that only these units (and the magnitude of preparation) is acceptable to the HPCUS. In fact, as long as the 1 in 10 parts is faithfully adhered to, the HPCUS is unconcerned if the scale of production required the measurements to be 1 kg in 10 kg, or 0.2 ml in 2 ml, or 5 gallons in 50 gallons, or ½ oz. in 5 oz. The units and magnitude are not critical for the homeopathic process (though they are necessary and important considerations for the intended setting in which the attenuation is being made); however, the ratio must be faithfully adhered to, in order for the resulting product to comply with the HPUS.
b. The absence or use of trailing zeros after the decimal place implies a degree of precision that may or may not be applicable or attainable within the setting where the attenuation is being made. For instance, large scale manufacturing in tanks requires different equipment and measurement devices than health care practitioners would in their office.
Thus, after lengthy discussion, the Council on Pharmacy concluded that the methods employed in each setting must be appropriate and validated for that particular setting. Further, the equipment utilized (including, but not limited to Class A analytical glassware; balances / scales; pipettes and pipetors, flow meters, etc.) must be of appropriate accuracy and precision for the scale of production and properly calibrated. Within each setting, the manufacturer (or pharmacy, or practitioner) must set and document a justifiable level of variance and degree of accuracy and precision appropriate to the scale and equipment used in their operation. Further, the overall variance from start to finish must lie within an acceptable and justifiable range, which is dependent on the scale and equipment used.
1 For the sake of brevity, the examples are for decimal attenuations. The same criteria and rationale holds true for centesimal attenuations – using a 1 in 100 ratio.
2 E.g. “...the first decimal attenuation (1X) is prepared using one (1) part of medicinal raw material in a total of ten (10) parts of finished first decimal attenuation....”