Should we be concerned about herbal remedies

Abstract

During the latter part of this century the practice of herbalism has become mainstream throughout the world. This is due in part to the recognition of the value of traditional medical systems, particularly of Asian origin, and the identification of medicinal plants from indigenous pharmacopeias that have been shown to have significant healing power, either in their natural state or as the source of new pharmaceuticals. Generally these formulations are considered moderate in efficacy and thus less toxic than most pharmaceutical agents. In the Western world, in particular, the developing concept that ‘natural’ is better than ‘chemical’ or ‘synthetic’ has led to the evolution of Neo-Western herbalism that is the basis of an ever expanding industry. In the US, often guised as food, or food supplements, known as nutriceuticals, these formulations are readily available for those that wish to self-medicate. Within this system, in particular, are plants that lack ethnomedical verification of efficacy or safety. Unfortunately there is no universal regulatory system in place that insures that any of these plant remedies are what they say they are, do what is claimed, or most importantly are safe. Data will be presented in this context, outlining how adulteration, inappropriate formulation, or lack of understanding of plant and drug interactions have led to adverse reactions that are sometimes life-threatening or lethal.

Introduction

During the latter part of the 20th century herbalism has become mainstream worldwide. This is due in part to the recognition of the value of traditional and indigenous pharmacopeias, the incorporation of some derived from these sources into pharmaceuticals (DeSmet et al., 1992a, DeSmet, 1997, Winslow and Kroll, 1998), the need to make health care affordable for all, and the perception that natural remedies are somehow safer and more efficacious than remedies that are pharmaceutically derived (Bateman et al., 1998, Murphy, 1999). For a variety of reasons more individuals are nowadays preferring to take personal control over their health, not only in the prevention of diseases but also to treat them. This is particularly true for a wide variety of chronic or incurable diseases (cancer, diabetes, arthritis) or acute illnesses readily treated at home (common cold etc.) (Kincheloe, 1997). In this respect many individuals have become disenchanted with the worth of allopathic treatments, and the adverse effects that can be anticipated. They are seemingly unaware of the potential problems associated with herbal use or the fact that their limited diagnostic skills, or of those prescribing treatment for them, may prevent the detection of serious underlying conditions like malignancies (Saxe, 1987, Youngkin and Israel, 1996, Donaldson, 1998, Winslow and Kroll, 1998, Shaw et al., 1999, Stewart et al., 1999).

Most allopathic practitioners have traditionally considered herbal treatments to be innocuous or alternately, potentially problematical. Three decades ago only a few had any appreciation of the number of remedies that had their origins in herbal medicine and most had a vague impression of what herbalism, or other forms of alternate medicinal practices implied (Lipp, 1996). There was still a great deal of carry-over from the beginning of the 20th century when the introduction of wire services allowed for the dissemination of adverse effects of ‘snake-root’ concoctions and the like. As early as 1906, misbranding and adulteration were disallowed in the US Herbal remedies, not a part of ‘The Dispensatory of the United States of America’, were shunned as if the danger associated with one remedy was common to all much like the notion that if ‘one mushroom is poisonous, all must be’ and by 1938, safety testing was mandated under the Federal Food, Drug and Cosmetic Act. By mid-century, pharmacognosy (study of plants affecting health) was a dying science. Dicta of the day, as outlined in a 1962 law (Kefauver–Harris Drug Amendments) required proof of safety and efficacy. This policy determined that only chemically defined and clinically evaluated medicines had value, and if pharmaceutically derived, must be prescribed by allopathic physicians. (Murphy, 1999). Licensure to practice in the US was confined to allopathic clinicians and others in naturopathy and homeopathy whose traditional use of herbs was well defined. Some leeway was also given to practicing traditional healers within Asian and indigenous communities. On the whole, other types of herbalists were not recognized (O'Hara et al., 1998).

Such was the case for decades, until the ‘age of Aquarius’ arrived, and the ‘return to nature’ was the driving force of every ‘flower child’. In this wake, self-medication became the rule as old European herbals and indigenous remedies were revisited, and were used with impunity, without concern for adverse effects. In addition, hallucinogens, particularly from American indigenous cultures, became popular as many trying to escape the reality of a war-torn and ‘hide-bound’ world, experimented with ‘altered states’. Soon ‘health food stores’ appeared, specializing in unrefined food, organic-grown vegetables, herbs and herbal preparations. With the opening up of Asian markets, other types of medicines were introduced, and were permitted since they were considered already ‘culturally acceptable’. A synthesis of all these types of herbal medicinal practices evolved into what can be called, ‘Neo-Western’ herbalism. Formulae found in this system are based upon both ethnomedical worth or are simply serendipitous inventions of the formulator. A belief of benefit over single-ingredient drugs is the corner stone of this form of herbalism that subscribes to the notion that ‘primary active ingredients in herbs are synergized by secondary compounds, and secondary compounds mitigate the side effects caused by primary active ingredients’ (McPartland and Pruitt, 1999). Since it is possible for single taxa to contain a family of related bioreactive compounds varying in potency, it is logical to presume that one or more of these will contribute to the totality of the effects observed (Lewis and Elvin-Lewis, 1994, Elvin-Lewis and Lewis, 1995). It would follow that when mixtures of several crude extracts are used in formulations, enhancement of beneficial effects (or greater toxicity) is expected through either synergistic amplification or diminishment of possible adverse side effects. It is also presumed that their combination could prevent the gradual decline in efficacy that is frequently observed when single drugs are given over long periods of time (Borchers et al., 1997). Nowadays such remedies can be still found in ethnic and health food stores, but are also available in pharmacies and grocery stores. Unfortunately there is no universal regulatory system that ensures that these remedies are what they say they are, do what is claimed, or most importantly, are safe (Angell and Kassirer, 1998, DeSmet, 1993, DeSmet et al., 1997).