What to Do for the Common Cold?

The problems with studying herbal supplements include product variability (both as to content of active ingredient as well as potential contaminants) and the wide variety of protocols used for any given indication.  For instance, some claim that the leaves are the active portion of the plant, rather than the root, seeds or flowers, or vice versa.  Others might claim that the manufacturing process removes the active ingredient.  As recently pointed out by the FDA, one also has to monitor for potential contaminants, some of which can be deadly in isolation while others are if taken in conjunction w/other meds & supplements.  Proponents might claim benefit due to chronobiology, in other words, some feel that it matters what time of day you take the supplement.  Or perhaps a loading dose is required.  Complicating the above for us non-botanists, many different plant species are known by a common name, ginseng, for instance.  With all these variables, it's no wonder that studies of herbal supplements have such disparate results.

In the latest salvo to be published tomorrow, the authors randomized 713 patients 12-80yo who self-presented w/upper respiratory symptoms, eg common cold, to either no treatment, unblinded echinachea pills, blinded echinacea pills, or blinded placebo pills.  They self-assessed the severity of their symptoms and underwent objective measures of their immune response.

While the results were not statistically significant, there was a trend towards better symptom scores and shorter duration of illness for those randomized to echinacea (although there was no difference noted with regards to impact upon immune response).  The good news to report is that the product studied was of good quality as per the American Botanical Society and the dose/regimen was appropriate.  The bad news is that given this information, one would have hoped for better statistically significant results.

Will the above results dissuade someone from taking echinacea for the common cold?  Probably not.  But I would certainly have great difficult recommending it to anyone over rest & fluids.  In the meantime, wash your hands religiously because the best way still to treat a cold is to prevent it in the first place.