Introduction to the pharmacoeconomics of herbal medicines

Antibacterial Compound Isolation and Characterization from the Plant Cynotis axillaris Schult

A novel flavone glycoside was isolated from the methanolic extract of Cynotis axillaris Schult. Various analysis and characterization techniques were used to determine its structure and properties. The compound exhibited a melting point range of 231-232 °C and had a molecular formula of C27 H30 O14 . Several spectral characterization techniques were employed to establish the isolated compound's structure. These included UV-visible spectroscopy, FT-IR, LC-ESI-MS, and NMR spectroscopy. Based on these analyses, the structure of the isolated compound was determined to be 5,7,4'-trihydroxyflavone-8-α-L-rhamnopyranoside-4'-O-β-D-galactopyranosyl. This structure indicates that it is a flavone glycoside consisting of a flavone (5,7,4'-trihydroxyflavone) moiety attached to a sugar molecule (galactopyranosyl) at position 4', which further bears a rhamnose group at position 8 of the flavone. In addition, to the structural characterization, the compound also demonstrated significant antibacterial efficacy against various bacterial pathogens, including Gram-positive bacteria such as Bacillus subtilis MTCC441 and Gram-negative bacteria such as Escherichia coli MTCC1098, Proteus vulgarize MTCC426, and Salmonella Typhimurium MTCC3224. The antimicrobial activity was evaluated by measuring the zone of inhibition in millimetres, which provides an indication of the compound's ability to inhibit bacterial growth. The study successfully identified and characterized a novel flavone glycoside from Cynotis axillaris Schult. and its antimicrobial activity.

A cohort study of therapeutic prescriptions after the end of phytotherapy drug reimbursement by French Social Security

PURPOSE

The reimbursement of phytotherapy drugs for the treatment of mild anxiety and insomnia ended in March 2006 in France. The aim of this study is to investigate the short-term impact of stopping phytotherapy reimbursement.

METHODS

We monitored the prescriptions of 27,422 patients who received hypnotic and sedative phytotherapy drug treatment at least once in the 12 months preceding the end of reimbursement and made contact with their prescribing physician at least once in the following 12 months. A control cohort was recruited from patients fulfilling the same inclusion criteria in the 24 months before de-reimbursement and their prescriptions in the following 12 months were monitored. The impact of the end of reimbursement is estimated comparing prescription switches in these cohorts.

RESULTS

Before the end of reimbursement, 7684 (28%) patients being prescribed delisted phytotherapy drugs had the relevant drug marketing authorization approval (DMAA) indications. Co-prescriptions of hypnotic and sedative drugs concerned 40% of patients. Of the 4646 DMAA patients exclusively prescribed phytotherapy, 640 (14%) switched to hypnotic or sedative drugs only after the end of reimbursement, 3266 (70%) stopped all treatments and 740 (16%) carried on with a non-reimbursed phytotherapy prescription. When compared to the control cohort, patients exposed to de-reimbursement were more likely to switch to psychotropic drugs (OR = 1.46).

CONCLUSIONS

Ending the reimbursement of common drugs on the basis of insufficient evidence regarding their effectiveness or the low level of severity of their target pathologies should be accompanied by information or advice to prescribing health care actors.

Patterns and prevalence of antidepressant drug use in the German state of Baden-Wuerttemberg: a prescription-based analysis

PURPOSE

Population-based data about patterns and prevalence of antidepressant drug use is limited in Europe and presently unavailable for Germany. Therefore, we have identified patterns and prevalence of antidepressant use among outpatients on a population-based scale in the German state of Baden-Wuerttemberg.

METHODS

We conducted a historical cohort study using a computerised prescription database referring to all members of the major German public health insurance company AOK. We assessed the prevalence of antidepressant drug use over a 3-year period, calculated the number of prescription items purchased per patient and compared first-line and second-line treatments.

RESULTS

The 1-year prevalence of antidepressant drug use among more than 4,000,000 health insurance members was 7.4% (male: 4.3%; female: 10.2%). Importantly, almost 40% of the patients received only a single prescription item from 2000 to 2002. Though the use of serotonin-reuptake inhibitors (SSRIs) markedly increased by about 65% within the study period, these are primarily used as second-line drugs and still much less frequently than St. John's wort or tricyclic antidepressants such as amitryptiline or doxepin.

CONCLUSIONS

The prevalence of antidepressant drug use is higher than previously reported for other European countries. The preferred use of St. John's wort and tricyclics over SSRIs and other modern-type antidepressants in Germany is quite unique in Europe and different from the US. The identified drug use pattern leaves a major room for improvement in view of the numerous single prescription items purchased.

Electrocardiographic and hemodynamic effects of Panax ginseng

OBJECTIVE

To determine whether Panax ginseng ingestion can acutely or chronically alter electrocardiographic parameters: PR, QRS, QT, QTc, and RR intervals, and QT and QTc interval dispersion. Effects of P. ginseng on blood pressure and heart rate also were evaluated.

METHODS

This is a prospective, randomized, double-blind, placebo-controlled study of healthy adults at the University of Connecticut. Thirty subjects were randomly allocated to receive 28 days of therapy with either P. ginseng extract 200 mg or placebo. Baseline 12-lead electrocardiograms (ECGs) were obtained. Subsequent ECGs were performed following study drug ingestion at 50 minutes, 2 hours, and 5 hours on days 1 and 28. Blood pressure readings were taken with each ECG.

RESULTS

P. ginseng ingestion increased the QTc interval by 0.015 seconds on day 1 at 2 hours compared with the placebo group (p = 0.03). It also reduced diastolic blood pressure from 75 +/- 5 mm Hg at baseline to 70 +/- 6 mm Hg at the same time point (p = 0.02). The observed effects are not believed to be clinically significant. No other statistically significant changes were found in electrocardiographic or hemodynamic variables on days 1 or 28.

CONCLUSIONS

P. ginseng, at doses of 200 mg of the extract daily, increases the QTc interval and decreases diastolic blood pressure 2 hours after ingestion in healthy adults on the first day of therapy.

Pharmacokinetics and bioavailability of herbal medicinal products

The use of herbs for treating various ailments dates back several centuries. Usually, herbal medicine has relied on tradition that may or may not be supported by empirical data. The belief that natural medicines are much safer than synthetic drugs has gained popularity in recent years and led to tremendous growth of phytopharmaceutical usage. Market driven information on natural products is widespread and has further fostered their use in daily life. In most countries there is no universal regulatory system that insures the safety and activity of phytopharmaceuticals. Evidence-based verification of the efficacy of HMPs (herbal medicinal products, botanicals) is still frequently lacking. However, in recent years, data on evaluation of the therapeutic and toxic activity of herbal medicinal products became available. The advances in analytical technology have led to discovery of many new active constituents and an ever-increasing list of putatively active constituents. Establishing the pharmacological basis for efficacy of HMPs is a constant challenge. Of particular interest is the question of bioavailability to assess to what degree and how fast compounds are absorbed after administration of HMPs. Of further interest is the elucidation of metabolic pathways (yielding potentially new active compounds), and the assessment of elimination routes and their kinetics. These data become an important issue to link data from pharmacological assays and clinical effects. Of interest are currently also interactions of herbal medicinal products with synthetically derived drug products. A better understanding of the pharmacokinetics and bioavailability of phytopharmaceuticals can also help in designing rational dosage regimens. In this review, pharmacokinetic and bioavailability studies that have been conducted for some of the more important or widely used phytopharmaceuticals are critically evaluated. Furthermore, various drug interactions are discussed which show that caution should be exercised when combining phytopharmaceuticals with chemically derived active pharmaceutical ingredients.