Botanicals—or plants—have been used as medicine for thousands of years, long before the manufactured pharmaceutical products that modern medicine now uses to treat medical problems. Recently, we have seen both increased interest from the public and increased acceptance of alternatives to Western medicine for many medical problems and conditions. Herbal medicine is drawing increased attention and has given a boost to the phytopharmaceutical market on a global scale. Major for-profit pharmaceutical companies recently have invested in herbal medicine. Worldwide, about 35,000 plant species are being used for medicinal purposes. European countries have embraced the use of botanicals, and the use of herbal medicine in the United States has been steadily increasing. In 2017, the potential global market for botanical extracts and medicines was estimated at several hundred billion dollars.(1)
Brief History of Botanicals
Medicinal plants, also called medicinal herbs, have been used for healing purposes since prehistoric times. The earliest historical records of herbs are found in the Sumerian civilization, where hundreds of medicinal plants, including opium, are listed on clay tablets.
The Ebers Papyrus, dating back to ancient Egypt around 1550 BCE, describes over 850 plants that were used as medicines. In 60 AD, the Greek physician Dioscorides documented over 1000 recipes for medicines in De materia medica. This formed the basis of pharmacopeias for the next 1500 years. Many pharmacologically active substances have been found in nature and are still used today in modern Western medicine, including the common drugs aspirin, digoxin, quinine, and opium.
Opioids have gotten a bad rap in the past two decades, because opioid overdoses result in nearly 100,000 deaths each year in the United States. However, opioids have been used for thousands of years. The Mediterranean region contains the earliest archeological evidence of human use of opioids; the oldest known seeds date back to earlier than 5000 BCE, with purposes such as anesthetics and ritual uses. Evidence from ancient Greece indicates that opium was consumed in several ways, including inhalation of vapors, suppositories, and combined with hemlock as a means for suicide.(2)
The Sumerian, Assyrian, Egyptian, Indian, Minoan, Greek, Roman, Persian, and Arab empires all made widespread use of opium, which was the most potent form of pain relief in ancient times and allowed ancient surgeons to perform prolonged surgical procedures. Opium is mentioned in the most important medical texts of the ancient world, including the Ebers Papyrus and the writings of Galen and Avicenna.
Medicinal plants are widely used in nonindustrialized societies, mainly because they are readily available and cheaper than modern medicines.
In the early Middle Ages, Benedictine monasteries preserved medical knowledge in Europe, translating and copying classical texts and maintaining herb gardens. The view of the place of plants in medicine was radically altered in the 19th century by the application of chemical analysis. Alkaloids were isolated from a succession of medicinal plants, starting with morphine from the poppy in 1806. In 1817, quinine was derived from the cinchona tree. As knowledge of chemistry progressed, additional classes of pharmacologically active substances were discovered in medicinal plants. Commercial extraction of purified alkaloids, including morphine, from medicinal plants began at the pharmaceutical company Merck in 1826. Synthesis of a substance first discovered in a medicinal plant began with salicylic acid in 1853. Drug discovery from plants continued to be important through the 20th century and into the 21st, with important anti-cancer drugs derived from yew and Madagascar periwinkle.
Even today, medicinal plants are widely used in nonindustrialized societies, mainly because they are readily available and cheaper than modern medicines. Around a quarter of the drugs prescribed to patients today are derived from medicinal plants. The World Health Organization estimates that 80% of the world’s population depends primarily on traditional medicine (including but not limited to plants); an estimated two billion people are largely reliant on medicinal plants.(3)
Difference Between a Pharmaceutical Medication and a Botanical
For botanicals to be listed as dietary supplements, certain criteria must be met. A dietary supplement is intended to be an addition to the diet; contains one or more dietary ingredients (e.g., vitamins, minerals, botanicals, or amino acids); is intended to be consumed by mouth as a pill, capsule, tablet, or liquid; and must be labeled as a dietary supplement as mandated in the Dietary Supplement Health and Education Act of 1994.(4)
A distinction must be made when marketing dietary supplements. They are classified as supplements because they cannot make claims to treat diseases. However, two botanical products have been approved to be labeled as prescription drugs: Veregen and Mytesi. Veregen was approved in 2006 to treat genital warts, and Mytesi was approved in 2012 to treat noninfectious diarrhea in patients with HIV/AIDS.(5)
Resistance to the Use of Botanicals
Although there is a growing amount of evidence-based research supporting botanicals, the healthcare profession continues to resist their widespread acceptance. A vigorous debate currently is occurring about whether botanical medicines are effective, and whether it is ever appropriate to use them in a modern medical setting. Some stated objections are that clinical studies of botanicals are of poor quality, limited by factors such as small sample sizes and limited duration of therapy.
Notably, similar criticisms also have been directed at clinical trials of pharmaceutical medicines. In fact, one recent study compared the quality of clinical trials using botanicals to matched trials using conventional medicines and came to the surprising conclusion that the method and reporting quality of Western clinical trials of herbal medicines were, on average, superior to that for conventional medicines.(6)
Another obstacle to the wide acceptance of botanical products is that conducting clinical trials is very expensive, and these plant products cannot be patented. As a result, there is very little financial motivation for major pharmaceutical companies to invest in research into botanical products.
Finally, botanicals face threats such as climate change, habitat destruction, and the possibility of overcollection to meet market demand.
Botanicals in American Healthcare
The use of plants for medicinal purposes has been increasing throughout the world, including the United States. Many of the drugs used in modern therapeutics are natural products and have been derived from plants.(7) Nearly 50% of drugs currently available in the last few decades have a natural origin, and nearly 30 anticancer drugs, including actinomycin D, paclitaxel, vincristine, dexamethasone, and tamoxifen, come from natural sources.(8)
The ill effects of many modern chemotherapeutic drugs have provoked increased interest in an alternative such as the use of botanical products.
The use of multiple botanical products in combination with other modalities provides symptomatic relief in addition to targeting the disease at the tissue level. Plant-based preparations usually are slow to act and provide relief gradually, in comparison with the drugs used in modern medicine.(9) However, the ill effects of many modern chemotherapeutic drugs have led to increased interest in an alternative such as the use of botanical products.
Increased adoption of botanicals may be an option for other conventional interventions such as enhancing cardiovascular function, enhancing the immune system, and alleviating common psychological symptoms such as insomnia, anxiety, and mild depression. Botanicals are popular because patients can self-medicate, have significantly reduced costs compared with conventional medication, and have fewer side effects associated with conventional medicines (especially in cases of chronic problems). In the United States, botanicals are being promoted increasingly on conventional media and also social media.(10)
Botanicals are attractive when conventional medicine is ineffective, especially for analgesia and for chronic conditions such as cancer and arthritis. The widespread use of botanicals as a prophylaxis for the prevention of cancer also is noteworthy.(11)
Additionally, the use of dietary supplements (containing natural products) has become very popular among cancer patients in the United States, and many patients begin using botanicals upon receiving a cancer diagnosis.(12)
Botanicals are prepared in a variety of ways and can be taken in the form of tinctures, essential oils, teas, syrup, ointments, salves, and tablets or capsules that contain a powdered form of the whole plant, part of the plant, or a dried extract. Unfortunately these substances have not been widely accepted by allopathic healthcare practitioners.(13)
Many physicians do not have knowledge regarding botanicals, which discourages clinical trials. Due to a lack of concrete evidence and scientifically robust studies evaluating their potential risks and benefits of botanical agents, oncologists find it challenging to advise patients regarding their use and their probable positive or negative impact when they advise regarding the use of other—more mainstream—treatment modalities such as radiotherapy, chemotherapy, hormonal therapy, and immunotherapy.(14)
The claims made by distributors of botanicals usually are not backed by any regulatory authority.
Many botanicals are undergoing clinical trials; these trials, however, have met with little success because of the study limitations.(15) As a result, physicians seldom recommend the use of botanicals for medical conditions. That leaves patients to learn about botanicals and their benefits and applications from television, the Internet, and social media. The claims made by distributors of botanicals usually are not backed by any regulatory authority. For example, the FDA currently has not approved any phytoproduct for cancer therapy. Although some botanicals have undergone Phase II trials, most of them have failed to enter follow-up Phase III trials.
Safety of Botanicals
For the most part, botanicals are safe. As with any medicinal management, the length of time for which botanicals are used is an important consideration. For example, phytosterol ester, which is used for cholesterol control, is one botanical that is intended to be used over a long period of time.(16) Other botanicals, which are used for weight control or enhancing the immune system during flu season or during the pandemic, are best used for a shorter duration of several weeks or months.
Another example is St. John’s wort, which is thought to be efficacious for some mental health problems and symptoms of menopause. However, it interferes with drugs such as immunosuppressants; contraceptives; cardiovascular, antiretroviral, and anticancer drugs; as well as drugs acting on the central nervous system.(17)
In certain instances, taking botanicals in conjunction with conventional medications may be dangerous and cause adverse effects. One example is that the active ingredient in St. John’s wort might affect the body’s ability to metabolize warfarin, potentially affecting the clotting mechanism.(18)
Physicians must inquire what botanicals, supplements, and herbals their patients are taking. Many botanicals have been in use for hundreds of years to treat medical conditions, but when taken in conjunction with conventional medication, botanicals may be responsible for adverse and unwanted effects. Physicians must be aware—and make their patients aware—that botanicals may interfere with conventional medications, making these medications ineffective or inducing unwanted side effects.
Bottom Line: In response to the growing popularity of botanicals, physicians must become knowledgeable about their medicinal value and be acutely aware of their side effects and their interactions with conventional pharmaceutical products. The time has arrived for physicians to consider the use of botanicals in health promotion and disease management. Although there is evidence that plants may have beneficial effects against diseases and medical conditions, the use of botanicals can only be realized after double-blind placebo-controlled trials have confirmed their safety and efficacy. In the future, botanicals may replace some conventional drugs or be used in combination with other drugs, enabling the integration of botanicals into contemporary medicine.
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