Antimicrobial Stewardship in Veterinary Practice: Guidelines and Implementation Barriers

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-11

Key Takeaways

• Antimicrobial stewardship in veterinary practice is defined as the judicious selection of antimicrobials based on confirmed or strongly suspected bacterial infection, utilizing the correct dose, route, and shortest effective duration, with a significant gap existing between guideline recommendations and actual prescribing behavior due to various implementation barriers.
• Key barriers to effective antimicrobial stewardship include limited diagnostic infrastructure, such as the unavailability or unaffordability of culture and susceptibility testing (AST), and economic constraints for owners, which frequently lead to empirical therapy being the default approach, particularly in acute conditions.
• Guideline quality in veterinary medicine is variable, with many lacking explicit evidence links or implementation strategies, necessitating a critical evaluation of their methodological rigor and applicability to clinical settings, as highlighted by AGREE II assessments of European small animal guidelines.
• Prescribing behavior is influenced by clinical judgment, diagnostic limitations, economic realities, and regulatory frameworks, with companion animal practitioners sometimes using broad-spectrum antibiotics of higher importance to human health more frequently than livestock veterinarians due to differing registration restrictions.
• Implementation science offers a path forward, emphasizing the need for structured stewardship programs that integrate dissemination, training, audit, and feedback mechanisms, adapting strategies from human healthcare to the unique economic and logistical realities of veterinary practice within a One Health framework.
• Common errors in antimicrobial prescribing include treating duration as fixed rather than conditional, selecting drugs by habit instead of predicted susceptibility and tissue penetration, and conflating clinical improvement with microbiological cure, all of which can be mitigated by structured prescribing records and periodic audits.

Antimicrobial stewardship in veterinary medicine is the coordinated set of activities that supports the selection of the right antimicrobial, at the correct dose, for the appropriate duration, and only when a bacterial infection is confirmed or strongly suspected. This article reviews the current state of stewardship guidelines across companion animal and production animal practice, examines the evidence base for their design, and analyzes the practical barriers that prevent their implementation in clinical settings. It is written for veterinary researchers and clinicians who need a structured understanding of why guidelines exist, how they are constructed, and why they so often fail to change prescribing behavior.

The clinical question this article addresses is direct: when a veterinarian reaches for an antimicrobial, what forces shape that decision, and which of those forces can be modified by guidelines, education, or institutional change? The answer requires examining guideline development methodology, prescribing behavior surveys, diagnostic infrastructure limitations, and the economic realities of veterinary practice. The article also situates veterinary stewardship within the broader One Health framework, since antimicrobial resistance in animal pathogens does not respect species boundaries and the international policy response reflects that interconnectedness.

At a Glance

The Scientific Basis for Stewardship Guidelines

Antimicrobial stewardship rests on a pharmacological and ecological rationale. Every antimicrobial exposure exerts selective pressure on bacterial populations, favoring the survival and proliferation of resistant clones. This selection occurs also at therapeutic concentrations but also at sub-inhibitory concentrations that may be present in environmental reservoirs through excretion of unmetabolized drugs. The environmental dimension of resistance selection has become a formal consideration in risk assessment, with methodologies now being developed to evaluate whether environmental antibiotic concentrations can directly select for resistant bacteria or increase the persistence of resistance determinants already present. These selective effects operate across human medicine, veterinary medicine, and environmental compartments, which is why international bodies frame the response as a One Health problem requiring coordinated action across species and sectors.

The clinical logic of stewardship follows from this ecological framework. If every prescription carries a population-level cost, then each prescription must be justified by evidence that a bacterial infection is present or highly probable, that the chosen drug is active against the likely pathogen, and that the duration of therapy is no longer than necessary. This logic is straightforward in principle but difficult in practice because veterinary clinicians frequently face diagnostic uncertainty, client financial constraints, and pressure to produce rapid clinical improvement.

Guideline Development and Quality Assessment

Stewardship guidelines translate the ecological rationale into condition-specific recommendations. The quality of these guidelines varies substantially, and the methods used to assess them matter for interpreting their clinical value. A 2021 evaluation of European small animal stewardship guidelines used the AGREE II instrument, a validated tool for assessing guideline development methodology across domains including scope and purpose, stakeholder involvement, rigor of development, clarity of presentation, applicability, and editorial independence. The review identified 15 guidelines from 11 European countries that met inclusion criteria, and the AGREE II analysis highlighted methodological limitations across the available documents. Many guidelines lacked explicit links between evidence and recommendations, did not describe systematic search methods, and did not address implementation barriers or auditing strategies.

The practical consequence of variable guideline quality is that clinicians cannot assume that a published guideline reflects a rigorous evidence synthesis. The ENOVAT network's framework of critical antimicrobial use principles provides a useful checklist for evaluating any guideline: the document should address whether antimicrobial therapy is indicated at all, whether the drug selected has the narrowest spectrum consistent with efficacy, whether the dose and route are optimal, and whether the duration is the shortest that achieves clinical cure. Guidelines that fail to address these elements, or that do so without transparent evidence links, should be treated with caution.

Prescribing Behavior and Its Determinants

Survey data from multiple countries reveal consistent patterns in veterinary antimicrobial prescribing. In Australia, a cross-sectional survey of 892 veterinarians found that antibiotics were prescribed in one third of consultations, with potentiated aminopenicillins the most commonly used class at 36% of prescriptions, followed by fluoroquinolones at 15% and first- and second-generation cephalosporins at 14%. Empirical therapy dominated acute conditions at 76%, while chronic conditions were more likely to receive culture-guided therapy. Third-generation cephalosporin use was markedly higher in cats at 16% compared with 2% in dogs, a pattern that may reflect perceived compliance difficulties with oral administration in cats and the availability of long-acting injectable formulations.

The Australian survey also identified species-sector differences that align with regulatory frameworks. Small companion animal veterinarians reported prescribing broad-spectrum antibiotics of higher importance to human health more frequently than livestock veterinarians, a finding attributed in part to antibiotic registration restrictions in production animals. This observation illustrates that prescribing behavior is shaped also by clinical judgment but also by the regulatory environment, which can either constrain or enable the use of specific drug classes.

Barriers to Guideline Implementation

The gap between guideline recommendations and clinical practice is explained by a set of recurring barriers that appear across different countries and practice types. Diagnostic infrastructure is the most frequently cited obstacle. In the Nigerian survey, 82% of veterinarians reported unavailability of veterinary laboratory services as a barrier to antimicrobial susceptibility testing, and 72% cited the owner's inability to pay for testing. Australian veterinarians similarly reported the cost of culture and susceptibility testing and the lack of access to rapid and affordable diagnostic tests as strong or moderate barriers to appropriate prescribing.

These findings point to a structural problem that guidelines alone cannot solve. A guideline that recommends culture-guided therapy is unhelpful when no laboratory exists within practical reach, or when the cost of testing exceeds the client's budget for the entire consultation. The implementation gap is therefore not primarily a knowledge deficit among veterinarians, although knowledge gaps do exist. The Nigerian survey found that only 21% of respondents could correctly define antimicrobial stewardship and 59.8% were unaware of the national action plan guidelines, indicating that educational outreach remains necessary. But even veterinarians with excellent knowledge of stewardship principles will struggle to apply them without diagnostic support.

A second category of barriers involves the social and economic context of veterinary practice. The Australian survey found that fear of losing clients and colleague pressure were not considered major barriers by respondents, but prophylactic antibiotic use was considered appropriate by 51% of Nigerian respondents when farm biosecurity was poor. This divergence reflects different production systems and different baseline expectations about disease prevention. In livestock practice, antimicrobial use is sometimes a substitute for biosecurity investment, and stewardship interventions must address farm management practices alongside prescribing behavior.

Implementation Science and the Path Forward

The persistence of these barriers has led to recognition that stewardship is fundamentally an implementation problem instead of a knowledge problem. Implementation science, which studies the methods and strategies that facilitate the uptake of evidence-based practices into routine care, has become a priority in infection prevention and control and antimicrobial stewardship. Expert consensus from the 2017 Geneva IPC-Think Tank identified four domains requiring attention: teaching implementation skills to health professionals, fostering implementation through policy making, developing national and international actions to build implementation capacity, and supporting translational research that bridges social science and clinical research.

For veterinary medicine, this means that stewardship programs must include also guideline development but also explicit strategies for dissemination, training, audit, and feedback. Guidelines should include sections on implementation elements, and professional curricula should teach implementation skills alongside clinical pharmacology. The international policy framework, including the One Health approach promoted by the World Health Organization and the animal health standards maintained by the World Organization for Animal Health, provides the institutional context for these efforts. The challenge for veterinary medicine is to adapt implementation strategies developed primarily in human healthcare settings to the very different economic and logistical realities of veterinary practice.

Clinical Stewardship Workflow: From Presentation to Prescription

A structured stewardship workflow begins before the antibiotic is selected. The sequence is consistent across species, but the weight given to each step shifts with production system, patient status, and available diagnostics.

The first decision point is whether antimicrobial therapy is indicated at all. For acute, non-septic conditions with a self-limiting course, supportive care alone may suffice. For chronic conditions, the threshold for empirical therapy should be higher, and the diagnostic workup more extensive. Australian survey data show that empirical therapy dominates acute presentations, with 76% of acute cases treated without culture, compared with 24% of chronic cases. That disparity is clinically rational, but it also marks the boundary where stewardship interventions have the most leverage: the chronic case that receives a third empirical course instead of a culture-guided one.

When therapy is indicated, the clinician must classify the case as empirical, targeted, or prophylactic. Empirical therapy is appropriate when the patient is unstable, the infection is likely bacterial, and the cost of waiting for culture exceeds the risk of broad-spectrum exposure. Targeted therapy follows culture and susceptibility results. Prophylaxis is reserved for defined perioperative windows or documented exposure events, not for compensating for poor biosecurity. In the Nigerian survey, 51% of veterinarians considered prophylactic use appropriate when farm biosecurity was poor, a position that inverts the stewardship hierarchy. Prophylaxis should never substitute for environmental or management corrections.

Case Classification and Diagnostic Thresholds

The table compresses the decision logic, but the operative principle is that each case type carries a different diagnostic obligation. A chronic pyoderma in a dog demands cytology and culture before systemic therapy. A respiratory outbreak in feedlot cattle may justify metaphylaxis based on historical farm susceptibility patterns, but the farm should have a current AST profile on file.

Culture and Susceptibility Testing as a Stewardship Instrument

Culture and susceptibility testing (AST) is the single most informative diagnostic step in stewardship, yet it remains underused. In the Nigerian survey, only 20% of veterinarians conducted AST frequently, with unavailability of laboratory services (82%) and owner cost constraints (72%) cited as the principal barriers. Australian practitioners reported similar friction: the cost of culture and the lack of rapid, affordable diagnostics ranked as the strongest barriers to appropriate prescribing.

The clinician should sample before the first dose whenever the patient is stable enough to wait. Once an antibiotic is administered, culture yield drops and susceptibility results become harder to interpret. For deep infections, abscesses, and body cavity effusions, sampling is straightforward. For respiratory and enteric disease, the sample type matters: transtracheal wash or bronchoalveolar lavage for pneumonia, not oropharyngeal swabs, fecal culture with toxin testing for enteritis, not random rectal swabs.

When AST results return, the clinician should select the narrowest agent with documented susceptibility, prefer agents with a low resistance selection risk, and avoid reporting or prescribing based on intermediate results as though they were susceptible. The European guideline review identified several critical principles of antimicrobial use that should frame this selection, including the preference for narrow-spectrum agents and the avoidance of drugs classified as highest priority critically important antimicrobials when alternatives exist.

Monitoring Parameters and Treatment Duration

Monitoring serves two distinct purposes: confirming clinical response and detecting treatment failure early enough to change course. The parameters differ by condition, but a core set applies across most bacterial infections.

Clinical parameters include temperature trend, appetite, mentation, and local signs of inflammation. Temperature should trend toward normal within 24 to 48 hours of effective therapy. Failure to improve within 48 to 72 hours warrants reassessment, not automatic escalation. The differential for non-response includes resistant infection, sequestered infection, non-bacterial disease, and incorrect diagnosis.

Laboratory monitoring depends on the drug and the organ system. For aminoglycosides, serial renal parameters and urinalysis are required. For prolonged beta-lactam therapy, periodic hematology and biochemistry are prudent. For any course exceeding the label duration, the clinician should document the reason and set a recheck date at the time of the initial prescription.

Treatment duration should be the shortest effective course, not a fixed calendar interval. Many bacterial infections in companion animals respond to 5 to 7 days of therapy, and some dermatological conditions require longer courses based on the depth of infection. The Australasian survey found substantial variation in duration choices across practitioners, which suggests that duration is as much a stewardship target as drug selection. For production animals, withdrawal periods must be verified against current label and regional regulatory references before any treated animal enters the food chain.

Documentation and Prescribing Records

The medical record is the stewardship instrument that outlasts the consultation. Every antimicrobial prescription should be documented with the indication, the drug, the dose, the route, the duration, and the basis for selection. If culture was performed, the results and the organizm should be recorded. If therapy was empirical, the record should state why culture was deferred.

For production animal practice, group-level records matter as much as individual records. The record should capture the number of animals treated, the batch or pen identification, the withdrawal period applied, and the outcome. These records support farm-level trend analysis and are required for certification schemes in several regions. The WOAH terrestrial animal health standards address responsible antimicrobial use and surveillance obligations that apply across member countries, and practice records should be structured to meet those expectations.

Barrier Analysis and the Stewardship Implementation Checklist

Implementation failure is rarely a knowledge deficit. The Geneva IPC-Think Tank concluded that the largest challenge in infection control and antimicrobial stewardship is not the absence of evidence-based measures but their implementation. The barriers fall into four domains: diagnostic access, economic constraints, behavioral factors, and structural or regulatory gaps.

The checklist below condenses the workflow into an actionable sequence. It is designed for clinic-level use and can be adapted to production practice by substituting group-level steps for individual patient steps.

1. Confirm a bacterial infection is present or strongly suspected before prescribing.
2. Classify the case as empirical, targeted, or prophylactic.
3. Sample for culture before the first dose when the patient is stable.
4. Select the narrowest agent consistent with the suspected or confirmed pathogen.
5. Avoid highest-priority critically important antimicrobials when alternatives exist.
6. Prescribe the shortest effective duration and set a recheck date.
7. Document indication, drug, dose, route, duration, and basis for selection.
8. Review the case at 48 to 72 hours if no clinical response.
9. For production animals, verify withdrawal periods and record group-level treatment data.
10. Review prescribing patterns at the clinic or farm level at least annually.

The checklist is a starting point, not a substitute for clinical judgment. The MSD Veterinary Manual and AVMA practice resources provide species-specific therapeutic guidance that should inform drug selection within this framework. The One Health context matters here as well: the WHO One Health Initiative and CDC One Health resources frame antimicrobial resistance as a cross-sector problem, which means the veterinary record may eventually feed into human health surveillance systems. Records kept to a defensible standard today will serve that purpose without retrofitting.

Recognized Complications and Failure Modes

Stewardship programs fail through predictable mechanisms. The most common is guideline non-adherence that goes undetected because prescribing records are incomplete or never audited. In companion animal practice, empirical therapy dominates acute presentations, with one Australian survey finding empirical antimicrobial use in 76% of acute cases, and third-generation cephalosporin use in cats exceeding that in dogs by a wide margin, a pattern that suggests guideline drift instead of deliberate clinical choice. Early detection requires periodic prescribing audits stratified by clinician, species, and drug class, with results reviewed openly instead of punitively.

A second failure mode is the decoupling of stewardship from diagnostic capacity. When culture and susceptibility testing is unavailable, unaffordable, or slow, clinicians default to broader empirical coverage. In the Nigerian veterinary survey, 82% of respondents cited unavailability of laboratory services and 72% cited owner inability to pay as key barriers to susceptibility testing. The corrective action is not simply exhortation but structural: establish standing laboratory relationships, negotiate reduced-cost panels for stewardship cases, and validate rapid sampling techniques that improve yield.

A third mode is the misuse of prophylaxis. Over half of Nigerian veterinarians surveyed considered prophylactic antibiotic use appropriate when farm biosecurity was poor. This reasoning inverts the stewardship hierarchy. Prophylaxis is not a substitute for biosecurity, it is an adjunct that should be justified only when infection risk remains elevated despite adequate preventive measures. Detection requires reviewing prophylaxis indications against written criteria at the time of prescribing, not retrospectively.

Common Errors and Corrective Actions

Less experienced clinicians typically make three recurring errors. First, they treat duration as fixed instead of conditional. The correct approach is to define the re-examination point and the clinical criteria that justify stopping, switching, or extending therapy at that point. Second, they select antimicrobials by habit or formulary position instead of by predicted susceptibility and tissue penetration. The corrective action is to require a written justification for each prescription that names the suspected pathogen, the drug's spectrum, and the reason this drug outranks narrower alternatives. Third, they conflate clinical improvement with microbiological cure, stopping therapy when the patient looks better even when the infection site has not been reassessed.

The discriminating check for all three errors is the same: a structured prescribing record that forces explicit entry of indication, drug, dose, route, duration, and re-assessment date. When the record cannot be completed, the prescription should not proceed.

Limitations of Current Evidence

The evidence base for veterinary stewardship remains uneven. Most published guidelines target dogs and cats in Europe, and a systematic review of European small animal guidelines found that only 15 guidelines from 11 of 40 countries met basic inclusion criteria, with AGREE II analysis revealing substantial methodological limitations. Livestock guidance is more developed in some regions but varies with production systems and regulatory frameworks. The WHO One Health framework and the WOAH terrestrial animal health standards provide international reference points, but neither supplies species-specific prescribing thresholds.

Expert opinion still differs on several points. The clinical significance of sub-inhibitory antibiotic concentrations in environmental selection for resistance is accepted in principle, but the methods for environmental risk assessment are still being standardized, and no consensus exists on what constitutes a safe predicted environmental concentration. Whether routine postoperative prophylaxis in clean surgery is ever justified remains contested. The role of rapid diagnostic tests in reducing empirical prescribing is promising but the cost-benefit ratio in practice settings has not been established across species.

Escalation and Referral Criteria

Referral or specialist consultation is warranted when infection fails to respond to first-line therapy despite appropriate sampling, when susceptibility testing shows resistance to all oral options, when the infection involves a site where poor penetration is likely, or when recurrent infection suggests an undiagnosed focus. Laboratory involvement is indicated earlier than most clinicians choose: before starting therapy in chronic or recurrent cases, not after treatment failure.

Regulatory reporting obligations vary by jurisdiction, but veterinarians should know which infections in their region are notifiable and which antimicrobial uses are restricted. The AVMA practice resources and the MSD Veterinary Manual provide species-specific guidance on recognizing reportable conditions and on the clinical reasoning that supports escalation. When in doubt about reporting requirements, contact the relevant authority before treating, not after.

Troubleshooting Table

Frequently Asked Questions

How can I implement stewardship when culture and susceptibility testing is unavailable or unaffordable?

When laboratory access is limited, stewardship shifts to judicious empirical selection based on the most likely pathogen, infection site, and local resistance patterns. The survey of Australian veterinarians on antibiotic prescribing identified the cost of culture and susceptibility testing and lack of rapid, affordable diagnostics as major barriers to appropriate prescribing. In these settings, reserve critically important antimicrobials for cases with confirmed or strongly suspected resistant infections, use the narrowest agent likely to be effective, and document the clinical rationale. Re-evaluate therapy at 48 to 72 hours and de-escalate or stop if the patient improves. The knowledge, attitudes and practices survey of Nigerian veterinarians reported that unavailability of veterinary laboratory services and owner inability to pay were key barriers to susceptibility testing, indicating this challenge is global instead of regional.

What should I do when a client pressures me to prescribe antibiotics without clear evidence of bacterial infection?

Client pressure is a recognized driver of inappropriate prescribing, although research on Australian veterinarians' prescribing behavior found that fear of losing clients was rated as a minor barrier by most respondents. Address the request directly by explaining why antibiotics are not indicated, what alternative treatments exist, and what signs would prompt re-evaluation. Provide a written aftercare plan with specific return criteria. Where a viral or self-limiting condition is likely, offer symptomatic treatment and schedule a recheck instead of dispensing antibiotics. If the client remains insistent, document the conversation and your clinical reasoning in the medical record. This approach preserves the therapeutic relationship while maintaining professional obligations to antimicrobial stewardship.

How do stewardship priorities differ between companion animal and food animal practice?

Companion animal practitioners more frequently prescribe broad-spectrum antibiotics of higher importance to human health, while livestock veterinarians face regulatory restrictions on antibiotic classes and must consider withdrawal periods and food safety. The Australasian Infectious Disease Advisory Panel survey of antimicrobial prescribing in dogs and cats found that third-generation cephalosporins were used more often in cats than dogs, illustrating species-specific prescribing patterns. In food animal practice, stewardship emphasizes population-level metrics, treatment protocols, and prevention through biosecurity and vaccination. The WHO One Health framework links these sectors because resistance selected in animals can affect human health through direct contact, foodborne transmission, or environmental spread. Both settings require documentation, but food animal records must also support withdrawal period verification and residue avoidance.

What records should I keep to support stewardship decisions and defend them later?

Maintain a prescribing record that includes the clinical diagnosis, diagnostic test results, antimicrobial chosen, dose, route, duration, and the rationale for any deviation from established guidelines. Note whether therapy was empirical or culture-guided and record the recheck plan. The European Network for Optimization of Veterinary Antimicrobial Treatment guideline evaluation emphasizes that structured guidelines support clinical decisions, and your records should demonstrate how those guidelines informed your choices. In food animal practice, records must also document treatment groups, withdrawal periods, and drug inventory. These records serve multiple purposes: continuity of care, audit readiness, regulatory compliance, and defense if a treatment outcome is questioned. Review prescribing patterns periodically to identify opportunities for improvement.

How can I introduce stewardship protocols in a practice where colleagues are not engaged?

Start with a single condition or drug class where prescribing variation is obvious and improvement is measurable. Present the European guideline quality assessment findings to show that many national guidelines have methodological limitations, which means local protocols tailored to your practice can be as defensible as published ones. Propose a simple protocol, collect baseline data, and share results at a staff meeting. The Geneva infection prevention and control think tank report identified implementation skills as a priority area in health care and noted that guidelines should include practical implementation sections. Engage one or two interested colleagues as champions instead of attempting to change the whole practice at once. Frame stewardship as improving patient outcomes and reducing treatment failures, not as criticism of existing habits.

How should I explain antimicrobial stewardship to a client who asks why their animal cannot have antibiotics?

Explain that antibiotics treat bacterial infections, not viruses or inflammation, and that using them unnecessarily can make future infections harder to treat. Use the analogy of a toolbox: you want to keep the most effective tools working for when they are truly needed. The CDC One Health resources describe how resistant bacteria can spread between animals, people, and the environment, which gives clients a broader reason to support judicious use. Be specific about what you are treating instead and what improvement should look like. If the client is concerned about cost, explain that avoiding unnecessary antibiotics saves money and that a recheck examination is often more valuable than a prescription. Written aftercare instructions reinforce the message and reduce phone calls later.

Related Clinical & Scientific Guides

• Wildlife Disease Surveillance: Designing and Implementing a One Health Program
• Biosecurity Risk Assessment for Livestock Operations: A Practical Framework
• Rabies Post-Exposure Prophylaxis in Veterinary Personnel

References and Further Reading

• Knowledge, Attitudes and Practices of Veterinarians Towards Antimicrobial Resistance and Stewardship in Nigeria.. 2020.
• Overview and Evaluation of Existing Guidelines for Rational Antimicrobial Use in Small-Animal Veterinary Practice in Europe.. 2021.
• Antimicrobial Prescribing in Dogs and Cats in Australia: Results of the Australasian Infectious Disease Advisory Panel Survey.. 2017.
• Implementation research for the prevention of antimicrobial resistance and healthcare-associated infections, 2017 Geneva infection prevention and control (IPC)-think tank (part 1).. 2019.
• Dawning of a new ERA: Environmental Risk Assessment of antibiotics and their potential to select for antimicrobial resistance.. 2021.
• Factors influencing the behavior and perceptions of Australian veterinarians towards antibiotic use and antimicrobial resistance.. 2019.
• WHO One Health Initiative. WHO.
• CDC One Health and Zoonotic Disease Resources. CDC.
• MSD Veterinary Manual, Professional Edition. MSD Veterinary Manual.

Related Articles

• Antimicrobial Stewardship in Food Animal Practice: Metrics and Benchmarks
• Food Safety Risk Assessment in Veterinary Practice
• Zoonotic Disease Risk Assessment in Veterinary Practice
• Antimicrobial Resistance Surveillance in Wildlife: Methods and Gaps
• One Health Approach to Antimicrobial Resistance: A Veterinary Perspective

This article is educational professional reference material for veterinary audiences. It is not a substitute for veterinary diagnosis, individual clinical judgment, current product labeling, or applicable regulatory requirements.