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Pharmacovigilance (abbreviated PV or PhV), also known as Drug Safety, is the pharmacological science relating to the collection, detection, assessment, monitoring, and prevention of adverse effects with pharmaceutical products. The etymological roots for the word "pharmacovigilance" are: pharmakon (Greek for drug) and vigilare (Latin for to keep watch). As such, pharmacovigilance heavily focuses on adverse drug reactions, or ADRs, which are defined as any response to a drug which is noxious and unintended, including lack of efficacy. (The condition, that this definition only applies with the doses normally used for the prophylaxis, diagnosis or therapy of disease, or for the modification of physiological function was excluded with the latest amendment of the applicable legislation.) Medication errors such as overdose, and misuse and abuse of a drug as well as drug exposure during pregnancy and breastfeeding, are also of interest (even without adverse event itself), because they may result in an ADR.
Information received from patients and healthcare providers via pharmacovigilance agreements (PVAs), as well as other sources such as the medical literature, plays a critical role in providing the data necessary for pharmacovigilance to take place. In fact, in order to market or to test a pharmaceutical product in most countries, adverse event data received by the license holder (usually a pharmaceutical company) must be submitted to the local drug regulatory authority. (See Adverse Event Reporting below.)
Ultimately, pharmacovigilance is concerned with identifying the hazards associated with pharmaceutical products and with minimizing the risk of any harm that may come to patients.
Pharmacovigilance has its own unique terminology that is important to understand. Most of the following terms are used within this article and are peculiar to drug safety, although some are used by other disciplines within the pharmaceutical sciences as well.
The activity that is most commonly associated with Pharmacovigilance (PV), and which consumes a significant amount of resources for drug regulatory authorities (or similar government agencies) and drug safety departments in pharmaceutical companies, is that of adverse event reporting. Adverse event (AE) reporting involves the receipt, triage, data entering, assessment, distribution, reporting (if appropriate), and archiving of AE data and documentation. The source of AE reports may include: spontaneous reports from healthcare professionals or patients (or other intermediaries); solicited reports from patient support programs; reports from clinical or post-marketing studies; reports from literature sources; reports from the media (including social media and websites); and reports reported to drug regulatory authorities themselves. For pharmaceutical companies, AE reporting is a regulatory requirement in most countries. AE reporting also provides data to these companies and drug regulatory authorities that play a key role in assessing the risk-benefit profile of a given drug. The following are several facets of AE reporting:
One of the fundamental principles of adverse event reporting is the determination of what constitutes an adverse event case. During the triage phase of a potential adverse event report, the triager must determine if the "four elements" of an AE case are present:
If one or more of these four elements is missing, the case is not a valid AE report. Although there are no exceptions to this rule there may be circumstances that may require a judgment call. For example, the term "identifiable" may not always be clear-cut. If a physician reports that he/she has a patient X taking drug Y who experienced Z (an AE), but refuses to provide any specifics about patient X, the report is still a valid case even though the patient is not specifically identified. This is because the reporter has first-hand information about the patient and is identifiable (i.e. a real person) to the physician. Identifiability is important so as not only to prevent duplicate reporting of the same case, but also to permit follow-up for additional information.
The concept of identifiability also applies to the other three elements. Although uncommon, it is not unheard of for fictitious adverse event "cases" to be reported to a company by an anonymous individual (or on behalf of an anonymous patient, disgruntled employee, or former employee) trying to damage the company's reputation or a company's product. In these and all other situations, the source of the report should be ascertained (if possible). But anonymous reporting is also important, as whistle blower protection is not granted in all countries. In general, the drug must also be specifically named. Note that in different countries and regions of the world, drugs are sold under various tradenames. In addition, there are a large number of generics which may be mistaken for the tradeproduct. Finally, there is the problem of counterfeit drugs producing adverse events. If at all possible, it is best to try to obtain the sample which induced the adverse event, and send it to either the EMA, FDA or other government agency responsible for investigating AE reports.
If a reporter can't recall the name of the drug they were taking when they experienced an adverse event, this would not be a valid case. This concept also applies to adverse events. If a patient states that they experienced "symptoms", but cannot be more specific, such a report might technically be considered valid, but will be of very limited value to the pharmacovigilance department of the company or to drug regulatory authorities.
Adverse event coding is the process by which information from an AE reporter, called the "verbatim", is coded using standardized terminology from a medical coding dictionary, such as MedDRA (the most commonly used medical coding dictionary). The purpose of medical coding is to convert adverse event information into terminology that can be readily identified and analyzed. For instance, Patient 1 may report that they had experienced "a very bad headache that felt like their head was being hit by a hammer" [Verbatim 1] when taking Drug X. Or, Patient 2 may report that they had experienced a "slight, throbbing headache that occurred daily at about two in the afternoon" [Verbatim 2] while taking Drug Y. Neither Verbatim 1 nor Verbatim 2 will exactly match a code in the MedDRA coding dictionary. However, both quotes describe different manifestations of a headache. As a result, in this example both quotes would be coded as PT Headache (PT = Preferred Term in MedDRA).
Although somewhat intuitive, there are a set of criteria within Pharmacovigilance that are used to distinguish a serious adverse event from a non-serious one. An adverse event is considered serious if it meets one or more of the following criteria:
Aside from death, each of these categories is subject to some interpretation. Life-threatening, as it used in the drug safety world, specifically refers to an adverse event that places the patient at an immediate risk of death, such as cardiac or respiratory arrest. By this definition, events such as myocardial infarction, which would be hypothetically life-threatening, would not be considered life-threatening unless the patient went into cardiac arrest following the MI. Defining what constitutes hospitalization can be problematic as well. Although typically straightforward, it's possible for a hospitalization to occur even if the events being treated are not serious. By the same token, serious events may be treated without hospitalization, such as the treatment of anaphylaxis may be successfully performed with epinephrine. Significant disability and incapacity, as a concept, is also subject to debate. Whereas permanent disability following a stroke, would no doubt be serious, would "complete blindness for 30 seconds" be considered "significant disability"? For birth defects, the seriousness of the event is usually not in dispute so much as the attribution of the event to the drug. And, finally, medically significant events is a category that includes events that may be always serious, or sometimes serious, but will not fulfill any of the other criteria. Events such as cancer might always be considered serious, whereas liver disease, depending on its CTCAE (Common Terminology Criteria for Adverse Events) grade—Grades 1 or 2 are generally considered non-serious and Grades 3-5 serious—may be considered non-serious.
This refers to ICSRs that involve a serious and unlabelled event (an event not described in the drug's labeling) that is considered related to the use of the drug. (Spontaneous reports are typically considered to have a positive causality, whereas a clinical trial case will typically be assessed for causality by the clinical trial investigator and/or the license holder.) In most countries, the timeframe for reporting expedited cases from the time a drug company receives notification (referred to as "Day 0") of such a case is 15 calendar days. Within clinical trials such a cases is referred to as a SUSAR (a Suspected Unexpected Serious Adverse Reaction). If the SUSAR involves an event that is life-threatening or fatal, it may be subject to a 7-day "clock". Cases that do not involve a serious, unlabelled event may be subject to non-expedited or periodic reporting.
Also known as SAE (Serious Adverse Event) Reporting from clinical trials, safety information from clinical studies is used to establish a drug's safety profile in humans and is a key component that drug regulatory authorities consider in the decision-making as to whether to grant or deny market authorization (market approval) for a drug. SAE reporting occurs as a result of study patients (subjects) who experience serious adverse events during the conducting of clinical trials. (Non-serious adverse events are also captured separately.) SAE information, which may also include relevant information from the patient's medical background, are reviewed and assessed for causality by the study investigator. This information is forwarded to a sponsoring entity (typically a pharmaceutical company) that is responsible for the reporting of this information, as appropriate, to drug regulatory authorities.
Spontaneous reporting is the core data-generating system of international pharmacovigilance, relying on healthcare professionals (and in some countries consumers) to identify and report any adverse events to their national pharmacovigilance center, health authority (such as EMA or FDA), or to the drug manufacturer itself. Spontaneous reports are, by definition, submitted voluntarily although under certain circumstances these reports may be encouraged, or "stimulated", by media reports or articles published in medical or scientific publications, or by product lawsuits. In many parts of the world adverse event reports are submitted electronically using a defined message standard.
One of the major weaknesses of spontaneous reporting is that of under-reporting, where, unlike in clinical trials, less than 100% of those adverse events occurring are reported. Further complicating the assessment of adverse events, AE reporting behavior varies greatly between countries and in relation to the seriousness of the events, but in general probably less than 10% (some studies suggest less than 5%) of all adverse events that occur are actually reported. The rule-of-thumb is that on a scale of 0 to 10, with 0 being least likely to be reported and 10 being the most likely to be reported, an uncomplicated non-serious event such as a mild headache will be closer to a "0" on this scale, whereas a life-threatening or fatal event will be closer to a "10" in terms of its likelihood of being reported. In view of this, medical personnel may not always see AE reporting as a priority, especially if the symptoms are not serious. And even if the symptoms are serious, the symptoms may not be recognized as a possible side effect of a particular drug or combination thereof. In addition, medical personnel may not feel compelled to report events that are viewed as expected. This is why reports from patients themselves are of high value. The confirmation of these events by a healthcare professional is typically considered to increase the value of these reports. Hence it is important not only for the patient to report the AE to his health care provider (who may neglect to report the AE), but also report the AE to both the biopharmaceutical company and the FDA, EMA, ... This is especially important when one has obtained one's pharmaceutical from a compounding pharmacy.
As such, spontaneous reports are a crucial element in the worldwide enterprise of pharmacovigilance and form the core of the World Health Organization Database, which includes around 4.6 million reports (January 2009), growing annually by about 250,000.
Aggregate, or periodic, reporting plays a key role in the safety assessment of drugs. Aggregate reporting involves the compilation of safety data for a drug over a prolonged period of time (months or years), as opposed to single-case reporting which, by definition, involves only individual AE reports. The advantage of aggregate reporting is that it provides a broader view of the safety profile of a drug. Worldwide, the most important aggregate report is the Periodic Safety Update Report (PSUR). This is a document that is submitted to drug regulatory agencies in Europe, the US and Japan (ICH countries), as well as other countries around the world. The PSUR was updated in 2012 and is now referred to in many countries as the Periodic Benefit Risk Evaluation report (PBRER). As the title suggests, the PBRER's focus is on the benefit-risk profile of the drug, which includes a review of relevant safety data compiled for a drug product since its development.
Some countries legally oblige spontaneous reporting by physicians. In most countries, manufacturers are required to submit, through its Qualified Person for Pharmacovigilance (QPPV), all of the reports they receive from healthcare providers to the national authority. Others have intensive, focused programmes concentrating on new drugs, or on controversial drugs, or on the prescribing habits of groups of doctors, or involving pharmacists in reporting. All of these generate potentially useful information. Such intensive schemes, however, tend to be the exception.
Risk Management is the discipline within Pharmacovigilance that is responsible for signal detection and the monitoring of the risk-benefit profile of drugs. Other key activities within the area of Risk Management are that of the compilation of Risk Management Plans (RMPs) and aggregate reports such as the Periodic Safety Update Report (PSUR), Periodic Benefit Risk Evaluation Report (PBRER), and the Development Safety Update Report (DSUR).
One of the most important, and challenging, problems in pharmacovigilance is that of the determination of causality. Causality refers to the relationship of a given adverse event to a specific drug. Causality determination (or assessment) is often difficult because of the lack of clear-cut or reliable data. While one may assume that a positive temporal relationship might "prove" a positive causal relationship, this is not always the case. Indeed, a "bee sting" AE—where the AE can clearly be attributed to a specific cause—is by far the exception rather than the rule. This is due to the complexity of human physiology as well as that of disease and illnesses. By this reckoning, in order to determine causality between an adverse event and a drug, one must first exclude the possibility that there were other possible causes or contributing factors. In addition, if the patient is on a number of medications, it may be the combination of these drugs which causes the AE, and not anyone individually. There have been a number of recent high profile cases where the AE led to the death of an individual. The individual(s) were not overdosed with any one of the many medications they were taking, but the combination there appeared to cause the AE. Hence it is important to include in your/one's AE report, not only the drug being reported, but also all other drugs the patient was also taking.
For instance, if a patient were to start Drug X and then three days later were to develop an AE, one might be tempted to attribute blame Drug X. However, before that can be done, the patient's medical history would need to be reviewed to look for possible risk factors for the AE. In other words, did the AE occur with the drug or because of the drug? This is because a patient on any drug may develop or be diagnosed with a condition that could not have possibly been caused by the drug. This is especially true for diseases, such as cancer, which develop over an extended period of time, being diagnosed in a patient who has been taken a drug for a relatively short period of time. On the other hand, certain adverse events, such as blood clots (thrombosis), can occur with certain drugs with only short-term exposure. Nevertheless, the determination of risk factors is an important step of confirming or ruling-out a causal relationship between an event and a drug.
Often the only way to confirm the existence of a causal relationship of an event to a drug is to conduct an observational study where the incidence of the event in a patient population taking the drug is compared to a control group. This may be necessary to determine if the background incidence of an event is less than that found in a group taking a drug. If the incidence of an event is statistically significantly higher in the "active" group versus the placebo group (or other control group), it is possible that a causal relationship may exist to a drug, unless other confounding factors may exist.
Signal detection (SD) involves a range of techniques (CIOMS VIII). The WHO defines a safety signal as: “Reported information on a possible causal relationship between an adverse event and a drug, the relationship being unknown or incompletely documented previously”. Usually more than a single report is required to generate a signal, depending upon the event and quality of the information available.
Data mining pharmacovigilance databases is one approach that has become increasingly popular with the availability of extensive data sources and inexpensive computing resources. The data sources (databases) may be owned by a pharmaceutical company, a drug regulatory authority, or a large healthcare provider. Individual Case Safety Reports (ICSRs) in these databases are retrieved and converted into structured format, and statistical methods (usually a mathematical algorithm) are applied to calculate statistical measures of association. If the statistical measure crosses an arbitrarily set threshold, a signal is declared for a given drug associated with a given adverse event. All signals deemed worthy of investigation, require further analysis using all available data in an attempt to confirm or refute the signal. If the analysis is inconclusive, additional data may be needed such as a post-marketing observational trial.
SD is an essential part of drug use and safety surveillance. Ideally, the goal of SD is to identify ADRs that were previously considered unexpected and to be able to provide guidance in the product's labeling as to how to minimize the risk of using the drug in a given patient population.
A Risk Management Plan (RMP) is a documented plan that describes the risks (adverse drug reactions and potential adverse reactions) associated with the use of a drug and how they are being handled (warming on drug label or on packet inserts of possible side effects which if observed should cause the patient to inform/see his physician and/or pharmacist and/or the manufacturer of the drug and/or the FDA, EMA), ...). The overall goal of an RMP is to assure a positive risk-benefit profile once the drug is (has been) marketed. The document is required to be submitted, in a specified format, with all new market authorization requests within the European Union (EU). Although not necessarily required, RMPs may also be submitted in countries outside the EU. The risks described in an RMP fall into one of three categories: Identified Risks, Potential Risks, and Unknown Risks. Also described within an RMP are the measures that the Market Authorization Holder, usually a pharmaceutical company, will undertake to minimize the risks associated with the use of the drug. These measures are usually focused on the product's labeling and healthcare professionals. Indeed, the risks that are documented in a pre-authorization RMP will inevitably become part of the product's post-marketing labeling. Since a drug, once authorized, may be used in ways not originally studied in clinical trials, this potential "off-label use", and its associated risks, is also described within the RMP. RMPs can be very lengthy documents, running in some cases hundreds of pages and, in rare instances, up to a thousand pages long.
In the US, under certain circumstances, the FDA may require a company to submit a document called a Risk Evaluation and Mitigation Strategies (REMS) for a drug that has a specific risk that FDA believes requires mitigation. While not as comprehensive as an RMP, a REMS can require a sponsor to perform certain activities or to follow a protocol, referred to as Elements to Assure Safe Use (ETASU), to assure that a positive risk-benefit profile for the drug is maintained for the circumstances under which the product is marketed.
Pharmaceutical companies are required by law in most countries to perform clinical trials, testing new drugs on people before they are made generally available. This occurs after a drug has been pre-screened for toxicity, sometimes using animals for testing. The manufacturers or their agents usually select a representative sample of patients for whom the drug is designed – at most a few thousand – along with a comparable control group. The control group may receive a placebo and/or another drug, often a so-called "gold standard" that is "best" drug marketed for the disease.
The purpose of clinical trials is to determine:
Clinical trials do, in general, tell a good deal about how well a drug works and what potential harm it may cause. They provide information that should be reliable for larger populations with the same characteristics as the trial group - age, gender, state of health, ethnic origin, and so on.
The variables in a clinical trial are specified and controlled, but a clinical trial can never tell you the whole story of the effects of a drug in all situations. In fact, nothing could tell you the whole story, but a clinical trial must tell you enough; "enough" being determined by legislation and by contemporary judgements about the acceptable balance of benefit and harm. Ultimately, when a drug is marketed it may be used in patient populations that were not studied during clinical trials (children, the elderly, pregnant women, patients with co-morbidities not found in the clinical trial population, etc.) and a different set of warnings, precautions or contraindications (where the drug should not be used at all) for the product's labeling may be necessary in order to maintain a positive risk/benefit profile in all known populations using the drug.
Pharmacoepidemiology is the study of the incidence of adverse drug reactions in patient populations using drug agents.
Although often used interchangeably, there are subtle differences between the two disciplines. Pharmacogenetics is generally regarded as the study or clinical testing of genetic variation that gives rise to differing responses to drugs, including adverse drug reactions. It is hoped that pharmacogenetics will eventually provide information as to which genetic profiles in patients will place those patients at greatest risk, or provide the greatest benefit, for using a particular drug or drugs. Pharmacogenomics, on the other hand, is the broader application of genomic technologies to new drug discovery and further characterization of older drugs.
Several organisations play a key collaborative role in the global oversight of Pharmacovigilance:
The Council for International Organizations of Medical Sciences (CIOMS), through its Working Groups, is a globally-oriented think tank that provides guidance on drug safety related topics. CIOMS is part of WHO and prepares reports that are used as a reference for developing future drug regulatory policy and procedures. Over the years, many of CIOMS' proposed policies have been adopted. Examples of topics these reports have covered include: Current Challenges in Pharmacovigilance: Pragmatic Approaches (CIOMS V); Management of Safety Information from Clinical Trials (CIOMS VI); the Development Safety Update Report (DSUR): Harmonizing the Format and Content for Periodic Safety Reporting During Clinical Trials (CIOMS VII); and Practical Aspects of Signal Detection in Pharmacovigilance: Report of CIOMS Working Group (CIOMS VIII).
The goal of ICH is to recommend global standards to be followed by drug companies and drug regulatory authorities around the world. The ICH (the International Conference on Harmonization) is a global organisation with members from the European Union, the United States and Japan. The ICH Steering Committee (SC) is the governing body that oversees the harmonisation activities. Since its establishment in 1990, each of its six co-sponsors—the European Union (EU), the European Federation of Pharmaceutical Industries and Associations (EFPIA), the Ministry of Health, Labor and Welfare (MHLW, Japan), the Japanese Pharmaceutical Manufacturers Association (JPMA), the US Food and Drug Administration (FDA), and the Pharmaceutical Research and Manufacturers of America (PhRMA)—has had two seats on the SC. Other parties have a significant interest in ICH and have been invited to nominate Observers to the SC. The three Observers are the World Health Organization (WHO), Health Canada and the European Free Trade Association (EFTA). The International Federation of Pharmaceutical Manufacturers Association (IFPMA) participates as a non-voting member of the SC.
The International Society of Pharmacovigilance (ISoP) is an international non-profit scientific organisation, which aims to foster Pharmacovigilance both scientifically and educationally, and enhance all aspects of the safe and proper use of medicines, in all countries. http://www.isoponline.org/
The principle of international collaboration in the field of pharmacovigilance is the principal basis for the WHO International Drug Monitoring Programme, through which over 100 member nations have systems in place that encourage healthcare personnel to record and report adverse effects of drugs in their patients. These reports are assessed locally and may lead to action within the country. Through membership of the WHO Programme one country can know if similar reports are being made elsewhere. Member countries send their reports to the Uppsala Monitoring Centre where they are processed, evaluated and entered into the WHO International Database. When there are several reports of adverse reactions to a particular drug, this process may lead to the detection of a signal – an alert about a possible hazard communicated to members countries. This happens only after detailed evaluation and expert review.
Drug regulatory authorities also play a key role in the national or regional oversight of Pharmacovigilance:
In Canada, pharmocovigilance is regulated by the Marketed Health Products Directorate of the Health Products and Food Branch (Health Canada).
In Egypt, Pharmacovigilance is regulated by the Egyptian Pharmacovigilance Center of the Egyptian Ministry of Health
In Iraq, Pharmacovigilance is regulated by the Iraqi Pharmacovigilance Center of the Iraqi Ministry of Health
The pharmacovigilance effort in the European Union is coordinated by the European Medicines Agency (EMA) and conducted by the national competent authorities (NCAs). The main responsibility of the EMA is to maintain and develop the pharmacovigilance database consisting of all suspected serious adverse reactions to medicines observed in the European Community. The system is called EudraVigilance and contains separate but similar databases of human and veterinary reactions. EMA requires the individual marketing authorization holders (drug companies), to submit all received adverse reactions in electronic form (save in exceptional circumstances). The reporting obligations of the various stakeholders are defined in the Community legislation, namely Regulation (EC) No 726/2004, and for human medicines, European Union Directive 2001/83/EC as amended and Directive 2001/20/EC. In 2002 Heads of Medicines Agencies agreed on a mandate for an ad hoc Working Group on establishing a European risk management strategy. The Working Group considered the conduct of a high level survey of EU pharmacovigilance resources to promote the utilization of expertise and encourage collaborative working.
Indian Pharmacopoeia Commission as National coordination Centre under Pharmacovigilance Program of India, Ministry of Health and Family Welfare, Government of India, is the Pharmacovigilance regulatory authority in India.
Reference: www.ipc.gov.in www.cdsco.nic.in
Scientists working on pharmacovigilance share their experiences, findings, innovative ideas and researches during the annual meeting of Society of Pharmacovigilance, India
In Japan, pharmacovigilance is regulated by the PMDA and MHLW.
In Uganda, pharmacovigilance is regulated by the National Drug Authority.
Most Latin American countries have high or medium levels of regulatory pharmacovigilance requirements, in line with international standards.
In the U.S., the drug industry is regulated by the FDA, which is the largest national drug regulatory authority in the world. The FDA authority is exercised through the enforcement of regulations published in the U.S. Code of Federal Regulations (CFR). The principal drug safety regulations are found in 21 CFR Part 312 (IND regulations) and 21 CFR Part 314 (NDA regulations). Pharmaceutical manufacturers, and the academic/non-profit organizations (such as RADAR and Public Citizen) also play a role in pharmacovigilance in the US. The rule-making process within the US federal government also permits significant input from the legislative and executive branches of the US government, which also play a role in determining FDA policy.
Despite receiving attention and necessary action by regulatory agencies like FDA and the European Union, there is a lack of substantial procedures regarding impending monitoring of drug concentrations in the environment and the palpable adverse effects. In 2006 a new concept of pharmacovigilance in environmental pharmacology, entitled as 'Pharmacoenvironmentology' was suggested by Syed Ziaur Rahman. It is a form of pharmacovigilance which deals specifically with those pharmacological agents that have impact on the environment via elimination through living organisms subsequent to pharmacotherapy
A medical device is an instrument, apparatus, implant, in vitro reagent, or similar or related article that is used to diagnose, prevent, or treat disease or other conditions, and does not achieve its purposes through chemical action within or on the body (which would make it a drug). Whereas medicinal products (also called pharmaceuticals) achieve their principal action by pharmacological, metabolic or immunological means, medical devices act by physical, mechanical, or thermal means. Medical devices vary greatly in complexity and application. Examples range from simple devices such as tongue depressors, medical thermometers, and disposable gloves to advanced devices such as medical robots, cardiac pacemakers, and neuroprosthetics.
Given the inherent difference between medicinal products and medical products, the pharmacovigilance of medical devices is also different from that of medicinal products. To reflect this difference, a classification system has been adopted in some countries to stratify the risk of failure with the different classes of devices. The classes of devices typically run on a 1-3 or 1-4 scale, with Class 1 being the least likely to cause significant harm with device failure versus Classes 3 or 4 being the most likely to cause significant harm with device failure. An example of a device in the "low risk" category would be contact lenses. An example of a device in the "high risk" category would be cardiac pacemakers.
Medical device reporting (MDR), which is the reporting of adverse events with medical devices, is similar to that with medicinal products, although there are differences. For instance, in the US user-facilities such as hospitals and nursing homes are legally required to report suspected medical device-related deaths to both FDA and the manufacturer, if known, and serious injuries to the manufacturer or to FDA, if the manufacturer is unknown. This is in contrast to the voluntary reporting of AEs with medicinal products.
The safety of herbal medicines has become a major concern to both national health authorities and the general public. The use of herbs in Traditional medicines continues to expand rapidly across the world. Many people now take herbal medicines or herbal products for their health care in different national health-care settings. However, mass media reports of adverse events with herbal medicines can be incomplete and, therefore, misleading regarding the use of herbal medicines. Nevertheless, it can be difficult to identify the causes of adverse events since the amount of data is generally less than with more traditional medicines since the requirements for adverse event reporting is far less stringent with herbal medications than it is with more traditional medicines.
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