Complementary and Alternative Medicine (CAM) Utilization by Howard University (HU) First Year Pharmacy Students: Survey and Review of Most Commonly Used Herbs
2 UnityPoint Health-St. Luke’s, Pharmacy Department, Iowa, USA, Email: [email protected]
3 Veterans Affairs Medical Center, Martinsburg, West Virginia University School of Medicine, Harpers Ferry, USA
Received Date: Oct 28, 2017 / Accepted Date: Nov 23, 2017 / Published Date: Dec 04, 2017
Citation: Hailemeskel B, Ziregbe E, Tran C, et al. Complementary and Alternative Medicine (CAM) Utilization by Howard University (HU) First Year Pharmacy Students: Survey and Review of Most Commonly Used Herbs. Curr Res Integr Med 2017;2(3): 37-41
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An electronic questionnaire was utilized to conduct a survey on complementary and alternative medicine (CAM) use among first year Howard University pharmacy students. 36 out of 49 completed the questionnaire for a response rate of 73.5%. 21 (58.3%) reported having used herbs or other supplements in the past 5 years with cranberry, garlic, ginger and ginseng topping the list. Prayer (48%) and Yoga (32%) were the most commonly utilized non-herbal CAM modalities. Our finding is consistent with other studies, including one by the same authors, that CAM is a widely practiced modality in diverse segments of the US population.
Survey and review; CAM; Herbs; Howard University first year pharmacy
Complementary and alternative medicine (CAM) is a collection of diagnostic and therapeutic practices not generally utilized in conventional medicine (1). CAM may include modalities such as herbal supplements, spiritual or physical practices, and Chinese medicine (1). The 2012 National Health Interview Survey (NHIS) revealed that approximately thirty-three percent of adults use CAM with natural products being the most popular (2). Natural products, which include herbals and botanicals, are defined as dietary ingredients under the Dietary Supplement Health and Education Act of 1994 (DSHEA). In contrast to prescription drugs, dietary supplements such as herbs may be produced and marketed without first demonstrating safety or efficacy; it is only when the Food and Drug Administration (FDA) proves that a supplement is unsafe that a product can be removed from the market (3,4). This paper evaluates in an alphabetical order the nine most commonly used herbs among first year pharmacy students at Howard University. These are black cohosh, cranberry, Echinacea, garlic, ginger, ginkgo, ginseng, milk thistle and saw palmetto.
Black cohosh (Actaea racemosa) is a native plant to North America. It is a member of the buttercup family with active ingredients that include actein and cimifugoside (5,6). Black cohosh is most commonly used for menstrual/ menopause related symptoms including hot flashes, cramps, bloating and mood changes despite a paucity of clinical studies to support its use in this setting (7). A randomized double-blind control trial on women with anxiety disorder due to menopause concluded that there was no difference in the reduction of anxiety for women on black cohosh compared to placebo (7). However, the American College of Obstetricians and Gynecologists (ACOG) still recognizes the utility of black cohosh in relieving menopausal symptoms (8). Other common uses of this herb are in induction of labor, arthritis and osteoporosis (5,6). Black cohosh is best avoided in children and pregnant and lactating women, although there is no clear evidence of adverse effects. There are no known major drug-herb interactions with black cohosh with the exception of a possible interaction with tamoxifen (6). The mechanism of action for black cohosh is not clear, but it is believed to have a modulatory effect on the estrogen receptor, and alternatively on serotonin receptors (8). Black cohosh is available in the form of capsules, tablets, tinctures, and extracts. No optimal effective dose has been established for black cohosh, but the commonly recommended initial adult dose is 20 mg to 80 mg (7,9). A clinical trial conducted by the National Center for Complementary and Integrative Health (NCCIH) demonstrated that those who have taken black cohosh for as long as 12 months did not experience serious harmful effects (10). Cranberry (Vaccinium macrocarpon) is a shrub native to North America and has been historically used by early settlers from England to treat bladder and kidney diseases (11). It is rich in antioxidants such as Vitamin C and flavonoids, and its mechanism of action is through the inhibition of the adherence of type 1 fimbriated Escherichia coli (11-13). Cranberry products have long been used to prevent urinary tract infections (UTIs) in premenopausal women and are widely available in the United States in a variety of formulations including juice, capsules, tablets, and powder (14,15). Several studies which had demonstrated the effectiveness of cranberries in reducing the number of symptomatic UTIs in women with recurrent infections (16,17) have been contradicted by a 2012 review of twenty-four clinical trials which concluded that cranberry juice and supplements do not prevent UTIs and that many of the existing studies were of poor quality (18). Cranberry may potentiate bleeding with blood thinners such as aspirin or warfarin, due to an ingredient similar to aspirin, salicylic acid (19).
Echinacea is one of the most widely used herbal products in the United States (20). There are nine known different species of Echinacea, and they contain different chemicals, such as glycoproteins, polysaccharides, alkamides, and volatile oils (20). For centuries, Echinacea has been used to treat scarlet fever, syphilis, malaria, and blood poisoning, but its popularity declined after the introduction of antibiotics (21). It is important to take the necessary precaution when using Echinacea products, because of the possible interactions with antifungal agents (e.g. econazole), immune-suppressants and caffeine (21). Studies suggest Echinacea contains ingredients which enhance the immune system, relieve pain, and provide anti-inflammatory, antiviral and antioxidant activity (22). Although treatment of common cold with Echinacea does not seem to be beneficial, there is some evidence that it may have a preventive effect (22). Commercially, Echinacea is available as tinctures, extracts, tablets, capsules and ointments. Its use for the treatment of upper respiratory tract conditions is not recommended in the pediatric population due to its lack of effectiveness and potential side effects (21,23).
Garlic (Allium sativum) is native to Central Asia and the Middle East and has been used for medicinal purposes since the 18th century (24). It has beneficial chemical components such as allicin (25) which has the ability to cross phospholipid bilayers, human red blood cell membranes, and biological or artificial membranes by interaction with sulfhydryl groups (26). Garlic has been used for atherosclerosis, dyslipidemia, hypertension and a variety of cancers (27-30). The formulations of garlic include tablets, soft gels and oils (31). Further studies are required to determine if garlic has any protective effects against stomach and colorectal cancer as separate meta-analyses by Fleischauer and Hu came to conflicting conclusions (32,33). Garlic may interact with birth control medications, cyclosporine, anticoagulants, protease inhibitors, and nonsteroidal anti-inflammatory agents (NSAIDs) (34-36).
Ginger (Zingiber officinale) has been used for centuries in China for medicinal and culinary purposes. The chemical components of ginger include gingerols and shogaols (37). Shogaol is a selective 5-HT3 receptor antagonist which accounts for its anti-emetic properties. It is therefore often used to prevent nausea and vomiting associated with pregnancy, motion sickness, and chemotherapy (38-42). A meta-analysis of clinical trials conducted by Thomson et al. showed that ginger produced a 5-fold likelihood of improvement in nausea and vomiting in early pregnancy (43). Ginger has also been commonly used for arthritis, pain, and heart disease (44,45). It is available as a fresh or dried root, capsule, tea, bread, and dried stick (46). Ginger also has anticoagulant, antihyperglycemic and antihypertensive properties and caution has to be exercised during concomitant use with prescribed medications that have similar effects (47-49).
Ginkgo (Ginkgo biloba) is a Chinese tree species with short branches and fan-shaped leaves (50). Although there are more than 40 components in ginkgo, flavonoids and terpenoids are the only two components that have medicinal benefits (51). Ginkgo has been commonly used for anxiety, Alzheimer’s disease, and intermittent claudication. It is available in several formulations, including capsules, tablets, and powders (52-56). A meta– analysis by Weinmann et al. showed ginkgo to be more effective than placebo in improving cognition in patients with Alzheimer’s disease as well as vascular and mixed dementia (57). Ginkgo can interact with a wide range of medications metabolized by the liver including anticonvulsants, antidepressants, calcium channel blockers, anticoagulants, alprazolam, ibuprofen, cyclosporine, thiazide diuretics, and trazodone (58-60).
Ginseng belongs to the genus Panax, and the roots have been used for many centuries for a number of health benefits (61). The American ginseng (Panax quinquefolius) and the Asian ginseng (Panax ginseng) have similar chemical makeup, and both contain ginsenosides, which are believed to contain medicinal properties (61,62). Ginseng is commonly used to reduce the risk of getting the cold or flu, and there have been various studies that suggest ginseng may help boost the immune system (63). In one study that compared ginseng to placebo for 12 weeks, the number of incidents of colds and symptoms of flu were two-thirds lower in the group that took ginseng (63). In addition to boosting the immune system, several studies suggest ginseng may also improve glucose metabolism, psychomotor function, and pulmonary disease; however, further studies of these benefits are needed (64). Ginseng is available as water and alcohol extracts, fresh root, dried root, tinctures, powders, capsules, and tablets (65). Despite the various studies that support its efficacy in treating different ailments, it has several possible interactions with blood thinning medications, and therefore concomitant use with the latter should be avoided (35). Adverse effects of ginseng include insomnia, tachycardia, decreased appetite, hypertension, euphoria, and neonatal death (35,61,62).
Milk thistle (Silybum marianum) is native to Southern Europe, Southern Russia, and Asia, but also grows in North and South America (66). Historically, milk thistle has been used to treat liver problems, such as cirrhosis and hepatitis, in addition to kidney and gallbladder ailments (67). Silymarin, the main component of milk thistle, is known to protect the liver from acetaminophen and alcohol toxicity (66). Although limited by a small sample size and variations in dosing and duration, some studies seem to suggest that milk thistle improves liver function and overall survival in people with cirrhosis (66,67). It is available as 120 mg or 240 mg capsules of silymarin, liquid extracts, or tinctures. Possible interactions of milk thistle with antipsychotics, phenytoin, and birth control pills have been documented (67) and side effects include stomach upset, diarrhea, rash, nausea and vomiting (68).
Saw palmetto (Serenoa repens) is a palm tree native to the United States (69). As a dietary supplement, it is commonly used to self-treat the symptoms of benign prostatic hyperplasia (BPH), chronic pelvic pain, decreased sex drive, and hair loss (69,70). Research has suggested it has anti-androgenic, anti-inflammatory, and anti-proliferative properties with similar effects to the alpha1 adrenergic blockers such as finasteride and dutasteride. Saw palmetto does not decrease prostate-specific antigen (PSA) levels (70). Due to its similar effects, concomitant use of saw palmetto with alpha-1 blocking agents is not recommended (71). More recently, there is a preponderance of evidence that Saw palmetto, even at higher doses, may not be better than placebo in its effectiveness in the treatment of BPH (70). Saw palmetto is available as dried berries, tea formulations, powder in capsules, tablets, liquid tinctures and liposterolic extracts.
The survey tool used in this investigation was adapted from a study published on the use of CAM among Ethiopian immigrants in the USA. The survey was distributed to 49 first year pharmacy students as part of Drug Informatics Course, a mandatory course for first year professional pharmacy students. The goal of the course was to provide skills and knowledge of the various biomedical literature sources, including those that are related to alternative medicine. One of the topics in the course was to identify commonly used herbal products and know the various free internet and subscription-based drug information resources. One of us (BH) delivered the class lectures, and data were collected during these sessions. Participation in the survey was voluntary and students were given the option to complete it during the allotted time in class or later at their discretion and submit it to the instructor. Statistical analysis was done using SPSS.
A total of 36 first professional year pharmacy students participated in the study for a response rate of 73.5%. Demographic data by age, gender, birth within or outside the US, level of education, annual income and medical insurance status of participants are shown in Table 1. As shown in Table 2, twenty-one respondents (58.3%) had taken supplements/herbals in the past 5 years with the most commonly reported being cranberry, garlic, ginger, ginseng, saw palmetto, gingko, echinacea, black cohosh, and milk thistle. Other treatment modalities used by the survey respondents were prayer 48% (12/25), yoga 32% (8/25), chiropractor 4% (1/25), acupuncture/ massage/biofeedback 4% (1/25) and others 12% (3/25). The frequency of the supplement/herbal use was at least once a week for 62.1% (18/29) of the respondents, at least once a month for 10.3% (3/29), at least once a year for 17.2% (5/29), and at least once in 5 years for 10.3% (3/29). The ailments that were being treated included skin/wound problems, cough/ cold/sore throat, headache, arthritis pain, gastritis and stomach pain and other conditions. Nineteen respondents (86.4%) reported benefiting from complementary modalities while three (13.6%) reported no benefits. Only two respondents (5.6%) experienced some side effects, such as nausea and vomiting while 26 (72.2%) reported none at all. A majority of the herbs and supplements 72% (18/25) were purchased from CVS/retail stores, while 12% (3/25) were obtained from herbal/nutrition stores. 8% (2/25) were purchased online while 4% each (1/25) came from friends and family or were imported from another country (Table 2).
|Characteristics||Valid Sample % (proportion)|
|21 – 30||83.3% (30/36)|
|31 – 40||11.1% (4/36)|
|Born in the USA|
|Level of prior education|
|Some college||14.3% (5/36)|
|Associate degree/diploma||8.6% (3/36)|
|MSc or higher||14.3% (5/36)|
|< $50,000||97.1% (33/36)|
|$100,000 - $150,000||2.9% (1/36)|
Table 1: Demographic data of HU first professional year pharmacy students who use CAM
Three of these studies demonstrated a reduction in the progression of noncalcified plaque volume associated with statin therapy (35,40,41). In addition, Inoue et al. showed that statin therapy results in a reduction of both plaque volume and necrotic core volume, implying improved plaque stability (42).
Recent randomized controlled trials have included assessments of coronary plaque from CCTA measurements, including plaque volume, composition and vulnerability (39,43). Auscher et al. showed that early aggressive lipid lowering therapy increases dense calcium volume, but did not significantly affect plaque volume in patients with acute myocardial infarction (43). Lo et al. demonstrated a reduction in non-calcified plaque volume and other high-risk plaque features in a small group of HIV-infected patients treated with statins (39).
Our survey established that a majority (58.3%) of first professional year pharmacy students used herbs and supplements over the last five years with 62% of them reporting a frequency of at least once a week. Retail stores such as CVS were the most common sources, and it is highly likely that ease of access (proximity, availability, price, hours of operation, etc.) contributed to this pattern. Although Howard University provides health insurance to all students and office visits are free with no co-pay, limited office hours and long wait times coupled with the rigorous schedule of pharmacy school may make the conventional clinics less desirable for non-serious ailments. The results of this survey also showed that self-treatment options and alternative therapies such as prayer and yoga are frequently used at a rate of 48% and 32%, respectively.
Regardless of the rational for using CAM, more than 85 percent of utilizers reported health benefits with only 2 experiencing side effects. As an overwhelming majority have been using CAM within the past 5 years, this practice is unlikely to be influenced by their training or education in pharmacy school. Moreover, the survey was conducted early in the year while the introductory class in herbal products is not offered until the end of the first didactic year at Howard University.
Cranberry was the most frequently used herb/supplement out of the nine listed in the survey. As it is most commonly used for urinary tract infection and approximately 50%-60% of women will develop UTIs in their lifetime (13), the female predominance of our respondents may have skewed the results. Garlic, ginger and ginseng were used in equal frequency. Other common ailments for which herbs/supplements were used include respiratory complaints, gastrointestinal tract symptoms, skin conditions and pain/arthritis (Table 2).
|Responses||Valid Sample % (Proportion)|
|Taken supplements in the past 5 years|
|No Response||2.8% (1/36)|
|Frequency of CAM Use|
|At least once a week||62.1 (18/29)|
|At least once a month||10.3 (3/29)|
|At least once a year||17.2 (5/29)|
|At least once in 5 years||10.3 (3/29)|
|Name of herbal/supplement used|
|Saw palmetto||8% (2/27)|
|Milk thistle||4% (1/27)|
|Black Cohosh||4% (1/27)|
|Other alternative therapies|
|Ailments leading to herbal/supplement use|
|Respiratory (cough/cold)||20% (1/5)|
|Stomach (e.g. gastritis, pain)||20% (1/5)|
|Skin/wound problems||20% (1/5)|
|Did complementary methods help?|
|Experienced side effects?|
|Only sometimes||5.6% (2/28)|
|Source where herbals/supplements were obtained|
|CVS/other retail stores||72% (18/25)|
|Herbal/nutrition stores||12% (3/25)|
|Online suppliers||8% (2/25)|
|Obtained from another country||4% (1/25)|
|How did you learn about the herbals/supplements?|
|TV commercials||8% (2/25)|
Table 2: CAM use pattern by HU first year pharmacy students
Our sample size was small in part due to the unusually few cohorts accepted to the Howard University Pharmacy Program last year. The survey was administered to first year students only, because the Drug Informatics Course was offered to this group. The exclusion of students from other didactic years also precluded the opportunity to interpret whether the knowledge and training obtained from pharmacy school influenced CAM use. Additionally, the herbs listed in this survey were preselected by the investigators, and the data collected may not reflect a true representation of the types of herbs used. Furthermore, since there is such great diversity within the college of pharmacy, data on the ethnicity of participants should have been collected, as cultural traditions may influence the perception of CAM use. There is an opportunity for a follow-up study to determine whether ethnic background influences CAM use by pharmacy students.
About 53% of HU first year pharmacy students had used CAM in the past five years. Cranberry was the most frequently use product at the rate of 16%, followed by garlic, ginger and ginseng, each at 12%. Other most frequently used CAM modalities included prayers (33%) and yoga (22.2%). The majority of the respondents (86.4%) reported health benefits from CAM and 72.2% did not experience adverse effects.
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