The history of veterinary applications of herbals and botanicals is long and well documented. For example, black and white hellebore (Helleborus niger and Veratrum album, respectively) was pierced through the ear of horses or sheep by the Roman physician Pliny in the 1st century AD, as well an in the early 20th century as a purgative, emetic, anthelmintic and parasiticide (although it caused death in many animals). Historical prescriptions for herbal use can be found in such diverse sources as the Chinese Yuan Heng liaoma jiand in the medicinal practices of the North American Indian. Botanical “horse medicines” were provided during the Civil War. Even as late as 1957, popular books continued to list such substances as aconite, belladonna, cinchone, ipecac, nux vomica (strychnine) and tobacco for veterinary use. However, more recently, such titles were in scant evidence until the latest revival of interest in the use of herbal and botanical veterinary remedies.
The active ingredients of some pharmaceuticals are identical to, or derivatives of, bioactive constituents of historic folk remedies. Herbal and botanical sources form the origin of as much as 30% of all modern pharmaceuticals. For example, aspirin (acetylsalicylic acid) is a derivative of salicylic acid, which, as salicin (salicyl alcohol plus a sugar molecule), occurs in the flower buds of the meadowsweet (spirea) and in the bark and leaves of several trees, notably the white willow (Salix alba). White-willow-bark extracts were used for centuries as a pain remedy. Quinine was an important anti-fever agent and was widely employed for the treatment of fever of virtually any origin.
However, the fact that herbal products were used throughout history may also overlook real problems. For example, in order to ingest one gram of salicin, the parent of salicylate drugs, and only about half as potent as aspirin, from willow bark, one would have to ingest at least fourteen grams of the bark. The tannins in willow bark, as well as salicin are very irritating to the stomach, so consuming this much bark would likely give you quite a bellyache.
Another significant problem is the natural variation in plants. Different species of the same plant may have active compounds of varying qualities. The potency of such compounds deteriorates at unknown rates. Different compounds have various absorption rates from the gastrointestinal tract and there are also variations from batch to batch depending on growing conditions.
In addition, the current usage of botanicals is quite different from their historical use. Historically, herbs were used in smaller amounts, as specific treatments (rather than prophylactically, in order to prevent health problems), in crude form (as opposed to enriched extracts) and not in association with other synthetic medications (removing concerns about interactions between herbs and drugs). The indications for using a given botanical were poorly defined. Dosages were, unavoidably, arbitrary because the concentrations of the active ingredient were unknown. Any number of contaminants may have been present. Most important, many of the remedies simply did not work, and some were harmful or even deadly. True plant identities are doubtful, both in regard to genus and species. The societal acceptability of risk in the treatment of disease was higher. The transmission of information was haphazard; herbalists copied extensively from one another over millennia and mixed accurate (by modern standards) information with nonsense, misconceptions and inaccuracies. Accordingly, it may not be possible to use the historical record as a guide for many of the currently advocated uses of herbal and botanical products.
The historical record is also rather sobering when it comes to considering the question of whether herbal and botanical products are effective medicines. Historically, herbal and botanical medicines were not responsible for any measurable improvement in human health. In 1900, life expectancy was 45 years; however, in 1996 it was 76.1 years. These dramatic changes were largely due to clean water, vaccination and the ability to control infections via pharmacology.
In addition, when discussing the historical efficacy of herbal medications, one must also ask the question. “Effective compared to what?” Medical treatments available at the time of wide herbal use, such as bleeding, or prescribing large doses of mercury salts, were largely ineffective. The use of a botanical product that didn’t kill a person immediately might be expected to be of less harm to the patient than other therapies that were available at the time.
The nature of the claims made for efficacy and the vague nature of the conditions treated makes it exceedingly difficult to objectively evaluate the true utility of the plant-based remedies employed throughout history. In the past, the emphasis for their use was on treatment of symptoms, rather than underlying disease conditions (which had yet to be identified) such as “liver malfunction” or “dropsy.” Elimination of the symptom, rather than elimination of the underlying problem, was the criterion used for treatment “success.” For example, if a fever went away after ingesting willow bark, the treatment would have “worked,” although the disease process that caused the fever might have continued on, unaffected by the treatment.
Using the historical record to advocate herbal medications really doesn’t work – there wasn’t really alternative, and people had little idea about the true causes of disease. Fortunately, most of the herbs that have significant potential for harm have been abandoned by the herbal industry. But just because they don’t do harm doesn’t mean that they’re any good!