Risk of Hemorrhage Associated with Co-Prescriptions for Ginkgo biloba and Antiplatelet or Anticoagulant Drugs

Ginkgo biloba in the management of the COVID-19 severity

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is linked with inflammatory disorders and the development of oxidative stress in extreme cases. Therefore, anti-inflammatory and antioxidant drugs may alleviate these complications. Ginkgo biloba L. folium extract (EGb) is a herbal medicine containing various active constituents. This review aims to provide a critical discussion on the potential role of EGb in the management of coronavirus disease 2019 (COVID-19). The antiviral effect of EGb is mediated by different mechanisms, including blocking SARS-CoV-2 3-chymotrypsin-like protease that provides trans-variant effectiveness. Moreover, EGb impedes the development of pulmonary inflammatory disorders through the diminution of neutrophil elastase activity, the release of proinflammatory cytokines, platelet aggregation, and thrombosis. Thus, EGb can attenuate the acute lung injury and acute respiratory distress syndrome in COVID-19. In conclusion, EGb offers the potential of being used as adjuvant antiviral and symptomatic therapy. Nanosystems enabling targeted delivery, personalization, and booster of effects provide the opportunity for the use of EGb in modern phytotherapy.

The Synergistic Effect of Ginkgo biloba Extract 50 and Aspirin Against Platelet Aggregation

Purpose

We aimed to investigate potential synergistic antiplatelet effects of Ginkgo biloba extract (GBE50) in combination with aspirin using in vitro models.

Methods

Arachidonic acid (AA), platelet activating factor (PAF), adenosine 5'-diphosphate (ADP) and collagen were used as inducers. The antiplatelet effects of GBE50, aspirin and 1:1 combination of GBE50 and aspirin were detected by microplate method using rabbit platelets. Synergy finder 2.0 was used to analyze the synergistic antiplatelet effect. The compounds in GBE50 were identified by UPLC-Q/TOF-MS analysis and the candidate compounds were screened by TCMSP database. The targets of candidate compounds and aspirin were obtained in TCMSP, CCGs, Swiss target prediction database and drugbank. Targets involving platelet aggregation were obtained from GenCLiP database. Compound-target network was constructed and GO and KEGG enrichment analyses were performed to identify the critical biological processes and signaling pathways. The levels of thromboxane B2 (TXB2), cyclic adenosine monophosphate (cAMP) and PAF receptor (PAFR) were detected by ELISA to determine the effects of GBE50, aspirin and their combination on these pathways.

Results

GBE50 combined with aspirin inhibited platelet aggregation more effectively. The combination displayed synergistic antiplatelet effects in AA-induced platelet aggregation, and additive antiplatelet effects occurred in PAF, ADP and collagen induced platelet aggregation. Seven compounds were identified as candidate compounds in GBE50. Enrichment analyses revealed that GBE50 could interfere with platelet aggregation via cAMP pathway, AA metabolism and calcium signaling pathway, and aspirin could regulate platelet aggregation through AA metabolism and platelet activation. ELISA experiments showed that GBE50 combined with aspirin could increase cAMP levels in resting platelets, and decreased the levels of TXB2 and PAFR.

Conclusion

Our study indicated that GBE50 combined with aspirin could enhance the antiplatelet effects. They exerted both synergistic and additive effects in restraining platelet aggregation. The study highlighted the potential application of GBE50 as a supplementary therapy to treat thrombosis-related diseases.

Substances of Interest That Support Glaucoma Therapy

Glaucoma is a multifactorial disease in which pro-apoptotic signals are directed to retinal ganglion cells. During this disease the conventional outflow pathway becomes malfunctioning. Aqueous humour builds up in the anterior chamber, leading to increased intraocular pressure. Both of these events are related to functional impairment. The knowledge of molecular mechanisms allows us to better understand the usefulness of substances that can support anti-glaucoma therapy. The goal of glaucoma therapy is not simply to lower intraocular pressure; it should also be to facilitate the survival of retinal ganglion cells, as these constitute the real target tissue in this disease, in which the visual pathway is progressively compromised. Indeed, an endothelial dysfunction syndrome affecting the endothelial cells of the trabecular meshwork occurs in both normal-tension glaucoma and high-tension glaucoma. Some substances, such as polyunsaturated fatty acids, can counteract the damage due to the molecular mechanisms - whether ischemic, oxidative, inflammatory or other - that underlie the pathogenesis of glaucoma. In this review, we consider some molecules, such as polyphenols, that can contribute, not only theoretically, to neuroprotection but which are also able to counteract the metabolic pathways that lead to glaucomatous damage. Ginkgo biloba extract, for instance, improves the blood supply to peripheral districts, including the optic nerve and retina and exerts a neuro-protective action by inhibiting apoptosis. Polyunsaturated fatty acids can protect the endothelium and polyphenols exert an anti-inflammatory action through the down-regulation of cytokines such as TNF-α and IL-6. All these substances can aid anti-glaucoma therapy by providing metabolic support for the cells involved in glaucomatous injury. Indeed, it is known that the food we eat is able to change our gene expression.

Traditional Chinese medicine: herb-drug interactions with aspirin

Traditional Chinese medicine (TCM)-based herbal therapies have gained increasing popularity worldwide, raising concerns of its efficacy, safety profile and potential interactions with Western medications. Antithrombotic agents are among the most common prescription drugs involved in herb-drug interactions, and this article focused on aspirin, one of the most widely used antiplatelet agents worldwide. We discussed herbs that have potential interactions by exploring Western and TCM approaches to thrombotic events. Common TCM indications for these herbs were also highlighted, including possible scenarios of their concurrent usage with aspirin. With greater awareness and understanding of potential herb-drug interactions, TCM and Western physicians may collaborate more closely to identify, treat and, most importantly, prevent adverse drug events.

Use of complementary and alternative medicine by patients with end-stage renal disease on haemodialysis in Trinidad: A descriptive study

BACKGROUND

Despite the paucity of scientific evidence, complementary and alternative medicine (CAM) is widely used for the prevention and treatment of illness, holistic care, and counteracting the adverse effects of conventional medicine (CM). This study investigates the use of CAM by patients with end-stage renal disease (ESRD) on haemodialysis.

METHODS

This quantitative study was conducted from November 1, 2014 to December 31, 2014 in the haemodialysis unit at San Fernando General Hospital (San Fernando, Trinidad). Face-to-face questionnaire-based interviews were held with101of 125 eligible patients (response rate, 80.5%) at the chairside during haemodialysis. The completed questionnaires were entered into a secure computer database. Data analysis included descriptive analysis, χ2 tests, and binary logistic regression analysis.

RESULTS

A minority of the patients were CAM users (n = 19; 18.8%). All 19 CAM users took medicinal herbs, 78.9% (n = 15) used spiritual therapy, and 10.5% (n = 2) used alternative systems. Medicinal tea (n = 15; 78.9%), garlic (Allium sativum) (n = 17; 73.7%), and ginger (Zingiber officinale roscoe) (n = 13; 68.4%) were the most commonly used medicinal herbs. Seven (36.8%) patients used Chinese herbal medicines and 3 (15.8%) patients used Aloe vera. All CAM users were willing to use CAM without supervision or monitoring by their doctors while receiving CM. The use of CAM could not be predicted by age, sex, ethnicity, education, religion, marital status, or employment. Nearly all (98%) patients were satisfied with CAM. More than one-third (36.8%) of patients did not disclose their use of CAM to their doctors, who were generally indifferent to such therapy.

CONCLUSIONS

The use of CAM by patients with ESRD was relatively infrequent. All patients used medicinal herbs, most patients used spiritual therapy, and a minority of patients used alternative systems. Complementary and alternative medicine was primarily used for spiritual reasons and the likelihood of its use was influenced by family, friends, and other patients. Patients continued using CM with one or more CAM therapies without informing their healthcare providers, which is a major health risk.

Potentially inappropriate medications in elderly ambulatory and institutionalized patients: an observational study

Background

The elderly are frequently exposed to drug related problems causing hospitalizations and increased costs of care. Information about Romanian prescribing practices among the elderly and potential medication associated- risks is lacking. The objective of this study was to identify and compare the most frequent potentially inappropriate medications (PIM) recommended to ambulatory and institutionalized Romanian elderly, through an observational retrospective design.

Methods

All reimbursed medications prescribed to a sample of ambulatory elderly accessing two community pharmacies and all medications recommended to a group of institutionalized elderly (urban facilities, Romania, same month) were analyzed. The STOPP/START criteria and the PRISCUS list were used for PIM identification and for classification as misprescribed, underprescribed or overprescribed -subtypes.

Results

The analysis involved 345 prescriptions recommended to ambulatory elderly and 91 medical files available for the institutionalized patients. The ambulatory elderly had a mean age of 74.8 years old and were daily exposed to a median number of 3 prescribed medications. The institutionalized elderly were older (mean age 80.77) received 8 medications daily and 69 % of them were functionally dependent. Cardiovascular and neuropsychiatric indications were the most frequent: 64.34 % and 18.55 % of the ambulatory prescriptions, 93.40 % and 41.75 % of the institutionalized patients’ medical files. 159 PIM were identified on 34.49 % of the ambulatory prescriptions. 82.41 % of the institutionalized patients’ medical files contained 140 PIM. The potential underprescribing of cardiovascular therapies was the most frequent PIM category on the ambulatory prescriptions (55.34 % of all PIM), while for the institutionalized patients’ medical files, the misprescribed and overprescribed PIM were those predominantly represented (62.14 % and 27.14 % of all PIM). In both subgroups of data, NSAIDs (56.66 % of ambulatory prescriptions and 35.63 % of institutionalized patients’ data) and benzodiazepines (26.66 % of ambulatory prescriptions and 24.13 % of institutionalized patient’s data) were predominantly misprescribed. Anticholinergics were rarely used (0.62 % of total PIM from ambulatory prescriptions, 2.14 % of total PIM from institutionalized patients’ data).

Conclusions

The PIM identified in both elderly groups suggested potential risks for the occurrence of adverse events specific to the elderly population. Larger studies, both observational and interventional, are needed to ensure a safer therapeutic approach.

Neuroprotection in Glaucoma

Glaucoma is a degenerative optic neuropathy characterized by retinal ganglion cell (RGC) loss and visual field defects. It is known that in some glaucoma patients, death of RGCs continues despite intraocular pressure (IOP) reduction. Neuroprotection in the field of glaucoma is defined as any treatment, independent of IOP reduction, which prevents RGC death. Glutamate antagonists, ginkgo biloba extract, neurotrophic factors, antioxidants, calcium channel blockers, brimonidine, glaucoma medications with blood regulatory effect and nitric oxide synthase inhibitors are among compounds with possible neuroprotective activity in preclinical studies. A few agents (such as brimonidine or memantine) with neuroprotective effects in experimental studies have advanced to clinical trials; however the results of clinical trials for these agents have not been conclusive. Nevertheless, lack of compelling clinical evidence has not prevented the off-label use of some of these compounds in glaucoma practice. Stem cell transplantation has been reported to halt experimental neurodegenerative disease processes in the absence of cell replacement. It has been hypothesized that transplantation of some types of stem cells activates multiple neuroprotective pathways via secretion of various factors. The advantage of this approach is a prolonged and targeted effect. Important concerns in this field include the secretion of unwanted harmful mediators, graft survival issues and tumorigenesis. Neuroprotection in glaucoma, pharmacologically or by stem cell transplantation, is an interesting subject waiting for broad and multidisciplinary collaborative studies to better clarify its role in clinical practice.

The effect of Ginkgo biloba extracts on the pharmacokinetics and pharmacodynamics of cilostazol and its active metabolites in healthy Korean subjects

AIMS

The primary objective of this study was to evaluate the effects of Ginkgo biloba extracts (GBE) on the pharmacokinetics of cilostazol and its metabolites. The secondary objective was to assess the effect of GBE on the pharmacodynamics of cilostazol.

METHODS

A randomized, double-blind, two-way crossover study was conducted with 34 healthy Korean subjects. All subjects were given an oral dose of cilostazol (100 mg) plus GBE (80 mg) or cilostazol (100 mg) plus placebo twice daily for 7 days. Plasma concentrations of cilostazol and its active metabolites (3,4-dehydrocilostazol and 4'-trans-hydroxycilostazol) were measured using liquid chromatography-tandem mass spectroscopy on day 7 for pharmacokinetic assessment. The adenosine diphosphate-induced platelet aggregation and bleeding time were measured at baseline and on day 7 for pharmacodynamic assessment.

RESULTS

The geometric mean ratios of area under the concentration-time curve for dosing interval for cilostazol plus GBE vs. cilostazol plus placebo were 0.96 (90% confidence interval, 0.89-1.03; P = 0.20) for cilostazol, 0.96 (90% confidence interval, 0.90-1.02; P = 0.30) for 3,4-dehydrocilostazol and 0.98 (90% confidence interval, 0.93-1.03; P = 0.47) for 4'-trans-hydroxycilostazol. The change of aggregation after administration of cilostazol plus GBE seemed to be 1.31 times higher compared with cilostazol plus placebo, without statistical significance (P = 0.20). There were no significant changes in bleeding times and adverse drug reactions between the treatments.

CONCLUSIONS

Co-administration of GBE showed no statistically significant effects on the pharmacokinetics of cilostazol in healthy subjects. A large cohort study with long-term follow-up may be needed to evaluate the possible pharmacodynamic interaction between cilostazol and GBE, given that there was a remarkable, but not statistically significant, increase in inhibition of platelet aggregation.

Would It Matter to Expose Elderly Patients Who Took Digoxin to Chinese Medications?

OBJECTIVES

Elderly patients seem vulnerable to digoxin toxicity because of their diminished organ functions and tendency to encounter drug interactions. The aim of this research was to explore the extent of the concurrent use of digoxin with Chinese medications (CMs), its contributing factors, and the relevant consequences.

METHODS

A retrospective population-based cohort study was conducted using Longitudinal Health Insurance databases in Taiwan. Those elderly patients being prescribed with digoxin in outpatient settings in 2006 were evaluated for the incidence, prevalence, and duration of concurrent use with concentrated CMs in 2006. After 1:1 random matching to select the corresponding digoxin-only elderly users, univariate and multivariate logistic regression analyses were performed to explore factors associated with concomitant incident digoxin-CM use and incident digoxin-specific CM use. The relevant clinical and economic outcomes for a 3-month follow-up period from the initial exposure of incident digoxin-CM use were compared.

RESULTS

Of 185,076 elderly, 6,374 were prescribed with digoxin and 789 were CM-digoxin users in 2006. The prevalence and incidence of concomitant CM use among digoxin elderly users were 0.43% and 0.22%, respectively. Although the other factors were not statistically significantly associated with incident CM-digoxin use, patients with heart diseases and with benign prostate hypertrophy had an increased likelihood of incident CM-digoxin use of 115% and 102%, respectively. Almost all the concerned clinical and economic outcomes were not statistically significantly different between incident exposure or not, except for the use of potassium-sparing and nonsteroidal anti-inflammatory drugs.

CONCLUSIONS

There was a relatively low incidence of digoxin-CM use among the elderly in Taiwan. Although no significant effects on clinical and economic outcomes occurred, it is necessary to monitor potential side effects of digoxin more aggressively for those vulnerable elderly using digoxin with CMs, especially for those who tended to expose to incident digoxin-CM use elderly patients.

A review of potential harmful interactions between anticoagulant/antiplatelet agents and Chinese herbal medicines

Background

The risks attributed to drug-herb interactions, even when known, are often ignored or underestimated, especially for those involving anti-clotting drugs and Chinese medicines. The aim of this study was to structurally search and evaluate the existing evidence-based data associated with potential drug interactions between anticoagulant/antiplatelet drugs and Chinese herbal medicines (CHMs) and evaluate the documented mechanisms, consequences, and/or severity of interactions.

Methodology and Findings

Information related to anticoagulant/antiplatelet drug-CHM interactions was retrieved from eight interaction-based textbooks, four web resources and available primary biomedical literature. The primary literature searches were conducted in English and/or Chinese from January 2000 through December 2011 using the secondary databases (e.g., PubMed, Airiti Library, China Journal full-text database). The search terms included the corresponding medical subject headings and key words. Herbs or natural products not used as a single entity CHM or in Chinese Medicinal Prescriptions were excluded from further review. The corresponding mechanisms and severity ratings of interactions were retrieved using MicroMedex®, Lexicomp® and Natural Medicines Comprehensive Database®. Finally, we found 90 single entity CHMs contributed to 306 documented drug-CHM interactions. A total of 194 (63.4%) interactions were verified for its evidence describing possible mechanisms and severity. Of them, 155 interactions (79.9%) were attributable to pharmacodynamic interactions, and almost all were rated as moderate to severe interactions. The major consequences of these interactions were increased bleeding risks due to the additive anticoagulant or antiplatelet effects of the CHMs, specifically danshen, dong quai, ginger, ginkgo, licorice, and turmeric.

Conclusions/Significance

Conventional anticoagulants and antiplatelet drugs were documented to have harmful interactions with some commonly used single entity CHMs. For those patients who are taking conventional anti-clotting medications with CHMs for cardiovascular or cerebrovascular diseases, the potential risks of increased bleeding due to drug-CHM interactions should not be ignored.