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ORIGINAL ARTICLE
Should the use of omeprazole be allowed during
equestrian competition?
Madeleine L. H. Campbell
1
| Benjamin W. Sykes
2
1
School of Veterinary Medicine and Science,
University of Nottingham, Loughborough, UK
2
School of Veterinary Sciences, Massey
University, Palmerston North, New Zealand
Correspondence
Madeleine L. H. Campbell, School of
Veterinary Medicine and Science, University of
Nottingham, Loughborough, UK.
Email: madeleine.campbell@nottingham.ac.uk
Funding information
World Horse Welfare
Abstract
Background: Prioritising equine welfare, making evidenced-based policy, and
consistent decision-making across sports are crucial to maintaining the social licence
for equestrian sport. Regulations on the use of omeprazole during competition differ;
all regulators argue that their rules prioritise welfare. This discrepancy is a matter of
concern to the public and equestrian stakeholders.
Objectives: To apply Campbell's Ethical Framework for the use of Horses in Sport
to the question: ‘Should the use of omeprazole be allowed during equestrian
competition?’
Study design: A desk-based ethico-legal study.
Methods: Campbell's Ethical Framework for the Use of Horses in Sport was applied
in a stepwise fashion: definition of the ethical question; analysis of the evidence base;
consideration of stakeholders' interests; harm:benefit analysis; application of the
three central tenets of the framework, and formulation of conclusions and
recommendations.
Results: Stakeholders in equine sports have a variety of (frequently conflicting)
interests; all of them share an interest in optimising equine welfare. The incidence of
EGUS in competition horses is high. Omeprazole is a cornerstone treatment. There
are currently discrepancies in regulation about the use of omeprazole during compe-
titions. Recent evidence suggests that withholding omeprazole treatment for two
clear days before competition allows the recurrence of squamous EGUS, whereas
withholding treatment on the day of competition only does not have that effect.
Main limitations: The current state of scientific knowledge about the use of
omeprazole in horses. The analysis did not consider possible health and thus welfare
effects of the out-of-competition treatment with omeprazole.
Conclusions: Based on recent scientific evidence, if horses are being treated with
omeprazole outside of competition then treatment on the day of competition should
be permitted on welfare grounds. Revision of regulations around the use of
omeprazole during competition by governing bodies is necessary to safeguard the
ethical use of horses in sport.
Received: 20 February 2024 Accepted: 5 June 2024
DOI: 10.1111/evj.14129
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium,
provided the original work is properly cited.
© 2024 The Author(s). Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
Equine Vet J. 2024;1–8. wileyonlinelibrary.com/journal/evj 1
KEYWORDS
competition, ethics, horse, omeprazole, social licence, welfare
1|INTRODUCTION
The continuation of the social licence to use horses in sport is
increasingly under threat as wider public attitudes about the use of
non-human animals by humans evolve. There are a number of
elements of maintaining that social licence, including transparency
and trust.
1
Key amongst these elements is being able to communi-
cate to the non-equestrian public the welfare-based rationale for
decision-making around sports regulations. In this respect, it is
helpful not only if decision-making around rules and regulations is
transparent, but also if it is, wherever possible, consistent across
sports.
Campbell's previously published ‘Ethical Framework for the Use
of Horses in Sport’
2
provides a tool that can be used across
equestrian sports to not only enable but also publicly demonstrate
such consistent decision-making. Using this framework, regulatory
decision-making is informed by the scientific evidence base about the
welfare effects of any particular action under policy consideration.
Omeprazole is a proton pump inhibitor (PPI) that is commonly
used in veterinary medicine as a treatment for Equine Gastric Ulcer
Syndrome (EGUS), including both Equine Squamous Gastric Disease
(ESGD) and Equine Glandular Gastric Disease (EGGD). EGUS com-
monly occurs in horses that are intensively managed: clinical signs
may be absent or may include poor appetite, poor body condition,
poor performance, behavioural change, and abdominal discomfort.
3
EGUS affects horses in a wide range of equestrian disciplines includ-
ing showing, dressage, showjumping, eventing, endurance, western
disciplines and racehorses.
3
Prevalences of up to 100% and 65% for
Equine Squamous Gastric Disease and Equine Glandular Gastric Dis-
ease, respectively, have been reported in racing Thoroughbreds.
4,5
PPI
drugs reduce the production of acid in the equine stomach by impair-
ing the H
+
,K
+
, ATPase (proton) pump that normally secretes hydro-
chloric acid. In turn, this provides a favourable environment for
healing and alleviates the clinical signs of EGUS that impact negatively
upon equine welfare.
The use of omeprazole was identified in the literature as an area
of inconsistent regulation across equestrian sports as early as 2013.
6
The conundrum, and thus regulatory discrepancy, about whether or
not to allow the use of omeprazole during competition revolves
around a conflict between an ethical imperative to ensure that sport is
‘clean’and an ethical imperative to alleviate animal suffering when it
is possible to do so.
The ethos of ‘clean sport’, that is, sport being conducted with
athletes (whether human or non-human animals) free of drugs relates
to the ethical principle of justice.
7
This approach emphasises the idea
of ‘a level playing field’and, where betting on a sport takes place, of
‘punters’having confidence that no athlete has an ‘unfair’advantage
over another. It is further argued in the context of equestrian sport
that insisting that horses compete free of drugs (with a few
exceptions. See, e.g., the British Horseracing Authority's rules on
‘prohibited substances’)
8
protects equine welfare by disincentivising
attempted improvement of performance through pharmaceutical
means that might have adverse effects on the short- or longer-term
health and welfare of the horses treated. Such arguments form the
basis of regulations that do not allow the use of omeprazole during
competition.
Conversely, a welfare-based argument can be made in favour of
allowing the use of omeprazole during competition. This argument
can be rationalised by the ability to prevent a common disease that is
largely induced by management changes associated with training and
competing. ESGD and EGGD are both induced and exacerbated by
management in that both are prevalent in feral and non-exercising
populations, but the prevalence and severity of both ESGD and EGGD
increase with the onset of training.
9
Given the prevalence of EGUS in
horses in training and the apparent difficulty under common manage-
ment systems in reducing such prevalence through non-
pharmaceutical methods alone,
10
it can indeed be argued that failure
to use such a drug when it is available would be to allow ‘unnecessary
suffering’under the Animal Welfare Act (2006)
11
through an act of
omission.
The fact that regulators of international Thoroughbred racing and
the Federation Equestre Internationale (FEI) as a regulator of most
international-standard non-racing equestrian sports allow the use of
omeprazole outside of competition reflects the validity and accep-
tance of such welfare-based arguments. However, different regulators
have placed differing emphasis on the apparently conflicting ethical
imperatives to (i) conduct competition on a ‘clean sport’basis and
(ii) prevent unnecessary suffering through alleviating clinical symp-
toms where a drug is available to do so. This has led to a position
whereby the regulators of Thoroughbred racing do not allow the
use of omeprazole during competition whereas the FEI does, with
both arguing that their regulation best protects animal welfare.
This discrepancy in regulatory approach has continued to be an
issue of increasing concern and discussion, for example, at a British
Equine Veterinary Association meeting ‘Supporting champions’
themed on medication control held in 2023. Such concern is due
both to the direct relevance to equine welfare and because of the
damage that inconsistent, and therefore difficult-to-explain, regu-
lations might do to the maintenance of the social licence to use
horses in sport.
The ethical conundrum around the use of omeprazole in eques-
trianism was used as one example during initial stakeholder testing of
the Ethical Framework for the use of Horses in Sport.
12
The purpose
of that testing was not to reach a conclusion about the use of omep-
razole, but rather to test how well stakeholders were able to use the
framework tool, and to refine the tool according to stakeholder
2CAMPBELL and SYKES
feedback.
12
Thus any conclusions that stakeholders reached about
the use of omeprazole during the course of that testing were not ana-
lysed for publication.
It has hitherto not been clear, prima facie whether or not the use
of omeprazole during competition is ethical (and therefore ought to
be allowed) because there has been an insufficient evidence base
to resolve apparently equally valid and conflicting arguments that
(a) equine welfare (as well as sports integrity) is best protected by not
allowing the use of drugs during competition and (b) if a drug that can
relieve discomfort in competition horses without putting them at
exacerbated risk of injury is available it would be detrimental to
equine welfare not to use it. Recently, there have been significant
and pertinent developments in the scientific understanding of the
effects of withdrawal of equine omeprazole. In this article, with
particular reference to those recent developments, the authors
apply Campbell's Ethical Framework for the Use of Horses in
Sport
2
to the question of whether the use of omeprazole should
be allowed during equestrian competition. By using this standar-
dised tool, the authors hope to enable regulators to seek closer
alignment of their regulations on this issue, and thereby not only
serve equine welfare interests but also increase public confidence
in equestrian sport.
2|METHODOLOGY
2.1 |Step 1
Campbell's Ethical Framework for the Use of Horses in Sport
2
was
used to consider the defined question: ‘Is it ethical to allow the use of
omeprazole during competition?’The function of that framework has
been previously described in both its original
2
and a refined
10
form.
Briefly, the tool is centred on three ‘central tenets’and a stepwise
use of evidence and reflection to inform a consensus opinion. The
three central tenets are:
i. Minimisation of negative welfare and maximisation of positive
welfare for horses.
ii. Identification and prevention of avoidable, unnecessary risks to
horses.
iii. Compliance with governing body regulations and the law.
The stepwise function of the tool used to consider the question
‘Is it ethical to allow the use of omeprazole during competition?’is
illustrated in Figure 1.
2.2 |Step 2
The ‘relevant regulations and laws’were identified as international
and national laws that protect animals from ‘unnecessary suffering’
(e.g., the British Animal Welfare Act (2006)) and various sports regula-
tions. The latter are summarised in Table 1.
Identify relevant regulations and law:
International and national laws that
protect animals from ‘unnecessary
suffering’ and various sports’
regulations.
Identify and consider relevant evidence:
Scientific papers, consensus views
Identify stakeholders and their key
interests:
Table 2
Define the ethical question:
‘Is it ethical to allow the use of
omeprazole during competition?’
Apply the three central tenets:
Minimisation of negative welfare and
maximisation of positive welfare for horses.
Identification and prevention of avoidable,
unnecessary risks to horses.
Compliance with governing body regulations
and the law.
Reach conclusion; identify any conflicts
which cannot be resolved through
reference to the three central tenets;
make suggestions for resolution and for
future review of conclusion.
FIGURE 1 Schematic representation of the application of the
steps of Campbell's Ethical Framework for the Use of Horses in Sport
to the question: ‘Is it ethical to allow the use of omeprazole during
competition?’
CAMPBELL and SYKES 3
2.3 |Step 3
The application of the framework was informed through background
evidence accumulated via a search of PubMed and Web of Science
using the search terms: ‘omeprazole AND horses’; reference to allied
documents, for example, publication of consensus views, and detailed
reference to two recently published articles that address the issue of
possible rebound hyperacidity in horses whose omeprazole therapy is
discontinued.
13,14
2.4 |Step 4
Stakeholders in policy formation/regulation about whether or not the
use of omeprazole should be allowed in equestrian sport and their key
interests were identified as illustrated in Table 2.
2.5 |Step 5
The three central tenets were applied to the results of Steps 1–4.
2.6 |Step 6
A conclusion was reached based on the results of Steps 1–5. Resolu-
tion of conflicts through re-examining the evidence and the
harm:benefit analysis was attempted. Suggestions for resolution
and future review of the conclusion were made as described in
Sections 4and 5.
3|RESULTS
3.1 |Results of Steps 1–4 of the application of the
ethical framework
The peer-reviewed literature indicated that omeprazole does not
improve performance in horses without EGUS
15
and is an effective
treatment for ESGD and less effective for EGGD.
3,16–19
However, concerns have been raised as to the potential adverse
effects of omeprazole in the horse including rebound gastric hyper-
acidity that might occur with the discontinuation of treatment.
16
Treatment of horses with omeprazole causes an increase in serum
gastrin (hypergastinaemia) that is evident within 7 days of the initia-
tion of treatment.
20
The mechanism for this increase is that PPIs
increase intra-gastric pH and thus inhibit negative feedback on gastrin
production.
20
Gastrin regulates gastric acid secretion both through
direct effects on the parietal cells of the stomach and via
enterochromaffin-like (ECL) cells in the stomach.
13,21
In humans, but
not demonstrated in horses to date, hypergastrinaemia induced by
PPIs also has trophic effects on ECL-cells further worsening the
potential for rebound gastric hyperacidity.
This means that horses treated with PPIs, such as omeprazole,
have increased gastric pH due to the drug but simultaneously have
hypergastrinaemia that is signalling for increased acid secretion within
TABLE 1 List of key governing bodies in equestrian sport and their regulations around the use of omeprazole during competition.
Regulator Rule Effect of rule
Federation Equestre
Internationale
Equine Anti-Doping & Controlled Medication Regulations 2023
https://inside.fei.org/content/anti-doping-rules
Omeprazole allowed during competition
British Horseracing Authority Prohibited Substances Regulations 2023
https://www.britishhorseracing.com/regulation/anti-doping-
medication-control/prohibited-substances/
Detection time, omeprazole
https://www.britishhorseracing.com/wp-content/uploads/2019/
01/Detection-Time-for-omeprazole.pdf
Omeprazole not allowed during competition
Example international
regulators of horseracing
E.g., Racing Victoria https://www.racingvictoria.com.au/the-
sport/racing/rules-of-racing
E.g., International Federation of Horseracing Authorities https://
www.ifhaonline.org/
Omeprazole is exempt from prohibition on race
days
Screening limit stated. No specific statement of
required withholding period
Hurlingham Polo Association Rules and regulations for Polo (2023)
https://hpa-polo.co.uk/download/BB2022-Rules-Proof-4.pdf
Omeprazole allowed during competition
United States Equestrian
Federation
USEF Guidelines and Rules for Medications
https://www.usef.org/forms-pubs/2Zp2C_YKs4s/2022-equine-
drugs-medications
Omeprazole allowed during competition
Horseracing Integrity and
Safety Authority (USA)
Horseracing Integrity and Safety Authority Regulations
https://hisaus.org/regulations#controlled
The use of omeprazole is permitted up to 24 h
before racing (Rule 4212)
National Reining Horse
Association (USA)
National Reining Horse Association Animal Welfare and
Medications Policy
https://nrha.com/media/pdf/2023/welfare-meds-policy.pdf
Omeprazole is a ‘permitted medication’
Note: This list is not exhaustive but serves to elucidate the approach of key regulator stakeholders, and differences in those approaches.
4CAMPBELL and SYKES
the stomach. Thus, when treatment with omeprazole is discontinued
there is likely to be ‘rebound gastric hyperacidity’for as long as the
hypergastrinaemia (and thus the increased secretion of HCL from pari-
etal cells) persists.
14
Recent evidence suggests that the hypergastri-
naemia induced by omeprazole treatment lasts for only 2–4 days after
the discontinuation of treatment in horses that had received 57 days
of omeprazole treatment.
12
Hypergastrinaemia and rebound gastric hyperacidity are likely
explanations for the rapid recurrence of ESGD observed in horses
when omeprazole is discontinued. Recent research demonstrated a
return to pre-omeprazole treatment prevalence of ESGD when
omeprazole was stopped for 3 days (consistent with a ‘2 clear day’
regulatory withholding period), but not when treatment is withheld
for only 1 day (equivalent to a ‘day of racing’regulatory withholding
period).
10
Steps 1–4 inclusive of the application of the ethical framework
showed that:
•Whilst stakeholders in equine sports have a variety of (sometimes
conflicting) interests, all of them share an interest in optimising
equine welfare.
•The incidence of EGUS in horses competing across sports is high.
•Omeprazole is cornerstone of EGUS treatment and the manage-
ment of associated clinical signs.
•There is currently a discrepancy across equestrian sport in regula-
tion about the use of omeprazole during competitions, with all
regulators arguing that their rules best protect equine welfare.
•Recent evidence suggests that withholding omeprazole treatment
for two clear days before competition allows recurrence of
squamous ESGD, likely due to rebound gastric acidity, whereas
withholding treatment on the day of competition only does not
have that effect.
3.2 |Results of Step 5
Based on the results of Steps 1–4, to comply with the central tenets
of the ethical framework for the use of horses in sport on
(i) minimising negative welfare impacts and optimising positive welfare
impacts and (ii) not allowing avoidable, unnecessary suffering, medica-
tion should not be withheld from horses being treated with omepra-
zole for longer than the day of competition.
However, the use of omeprazole within ‘two clear days’of and
on the day of competition is not allowed within the current regula-
tions of some bodies governing horse sport.
3.3 |Results of Step 6
It is currently not possible for all equestrian sports to fulfil both the
welfare-based first two key considerations of the ethical framework
and the third, that is, complying with sports' governing body regula-
tions as some require that omeprazole is withdrawn from longer than
1 day before the competition. This discrepancy cannot be resolved by
re-examining the evidence or the harm:benefit analysis. Indeed, it
arises from the fact that recent scientific evidence has demonstrated
harms to equine health and welfare associated with persistent hyper-
gastrinaemia and rebound gastric hyperacidity that had not been pre-
viously reported in the literature.
4|DISCUSSION
In human sport, decisions around whether to allow the use of drugs
during competition are commonly presented in a ‘justice’ethical
framework
7
with the emphasis (whilst acknowledging that complete
equality of opportunity is impossible) being on preventing one athlete
having an unfair advantage over others. Similar sentiments are
expressed by the main regulators of equine sport.
22
The FEI website,
for example, states that the creation of ‘A universal and level playing
field’is one of its core values, whilst the website of the British
TABLE 2 Stakeholders in policy formation, and their key interests.
Stakeholder Stakeholder's key interests
Horses •Welfare sufficient to result in ‘A good life’
(https://equinewellbeing.fei.org/sf2023.html)
Regulators •Clean sport
•Protect equine welfare
•Maintain public confidence in the sport
•Maintain integrity to the sport for gambling
purposes
Riders/trainers •Competitive success
•Optimise the welfare of the horses who they
care for
•Career satisfaction
•Business viability
Owners •Competitive success
•Optimisation of the welfare of the horses
who they own
•Enjoyment of competitions
Equine welfare
organisations
•Optimisation of equine welfare
‘The public’•Confidence that the welfare of horses being
used in sport is properly protected
The gambling
public
•Confidence that the sport they are betting on
is ‘clean’
The veterinary
profession
•Fulfilment of their responsibility to safeguard
the health and welfare of animals under
their care.
•Business financial viability
•Professional satisfaction and development
Pharmaceutical
companies
•Medications are generally aimed at
promoting equine health and thereby welfare
•Maximisation of profits (brief withdrawal
period unlikely to have a significant impact
upon these)
Governments •Having national animal welfare legislation
upheld.
•Receiving tax revenue from gambling
CAMPBELL and SYKES 5
Horseracing Authority (BHA) claims that part of the BHA's role is to
‘encourage (…) the honest majority to do the right thing, and prevent
the dishonest minority from gaining an unfair advantage, thus ensur-
ing a level playing field for all’.
The principle of justice, however, is not sufficient to answer the
question of whether the use of omeprazole should be allowed in
equestrian competition, since the requirement for a ‘level playing
field’in this specific context could be satisfied either by not allowing
the use of omeprazole at all, or by allowing its use in all horses. This is
explained as follows: a blanket ban on the use of omeprazole during
competition theoretically ensures that no one horse has an
omeprazole-derived advantage over another, and thus satisfies the
principle of justice. However, the principle of justice could equally be
satisfied by allowing the use of omeprazole in all horses because
omeprazole functions to reduce EGUS and its associated clinical signs
(including poor performance) and negative welfare effects but not, so
far as is proven, to enhance athletic performance above that might be
expected in the same horse where it was healthy (i.e., not suffering
from EGUS). It, therefore, follows that if there were a blanket permis-
sion to use omeprazole during competition then all horses (i.e. horses
suffering from EGUS and treated with omeprazole, any horses that
were for some reason treated but did not have EGUS, and healthy
non-treated horses) could be considered to be competing at an
equally ‘normal’level of health, thus fulfilling the requirement for
justice.
The principle of justice is additionally insufficient to answer the
question of whether the use of omeprazole should be used in eques-
trian competition because it fails to take into account the vulnerability
of equine athletes. It is recognised that the consent of human athletes
to compete can be influenced by external pressures,
23
and that it is
thus an over-simplification to state that human athletes consent to
participate in sport and equine athletes do not. Nonetheless, the sec-
ond part of that statement, that is, that equine athletes are unable to
give informed consent to involvement in equestrian competition is
undeniably true. Equine athletes are in a vulnerable position and,
whether for deontological, Virtue Ethics or utilitarian reasons,
24
it is
incumbent upon the humans who use them in sport to optimise their
welfare.
Those involved in equestrian sport, therefore, need a method of
ethical analysis that prioritises equine welfare above all else, because
that is ‘the right thing to do’
25
and will thereby help to maintain the
social licence to use horses in sport. The use of the Ethical Framework
for the use of Horses in Sport provides such a method by combining
an essentially utilitarian analysis with a deontological requirement to
fulfil its three established key considerations.
The authors' application of Campbell's Ethical Framework for the
use of Horses in Sport to the question ‘Should the use of omeprazole
be allowed during equestrian competition?’showed that all stake-
holders share an interest in optimising equine welfare. It also con-
firmed that there are current regulatory discrepancies around the
question.
The review of the scientific and allied literature that provided the
evidence base for the analysis indicated that:
•EGUS occurs commonly in horses involved in competitive sport
•Omeprazole is a variably effective treatment for EGUS and allevi-
ates clinical signs that cause poor welfare and
•Withholding omeprazole treatment for longer than the day of com-
petition causes a deterioration in disease status. This can be
expected to result in an exacerbation of clinical signs and thus a
deterioration in welfare status
•In humans discomfort due to the rebound exacerbation of gastric
acidity that accompanies hypergastrinaemia at the time of abrupt
omeprazole withdrawal occurs rapidly.
20
To the best of our knowl-
edge, it is reasonable to expect a similarly rapid recurrence of
adverse clinical symptoms and therefore physical discomfort and a
negative welfare state in horses whose omeprazole treatment is
withdrawn for 1 day, even in the absence of the recurrence of
lesions within that timeframe. Therefore, whilst that expectation
remains to be proven through behavioural studies, the precaution-
ary principle should be followed: if horses are being treated with
omeprazole outside of competition then treatment on the day of
competition should be permitted on welfare grounds
5|CONCLUSIONS
Our analysis thus leads us to the following conclusions about whether
the use of omeprazole should be allowed during competition:
1. Given the insufficiencies (described above) of the principle of jus-
tice as a method of approaching this question, and given that the
use of omeprazole does not anyway enhance performance above
‘normal healthy’levels, ethical decision-making about whether or
not to allow the use of omeprazole during equestrian competition
should rely primarily upon the scientific evidence base about
health and welfare effects. Such evidence informs the application
of the Ethical Framework for the Use of Horses in Sport.
The scientific evidence shows that EGUS recurs if omeprazole treat-
ment is withdrawn ‘2 clear days’before competition. Based on that
scientific evidence withdrawal should be for not longer than 1 day.
There is no scientific evidence that omeprazole has an enhancing
effect on performance, and therefore no ‘level field of play’argu-
ment against permitting the use of omeprazole during competition.
It is highly likely—although it remains to be proven through beha-
vioural studies—that horses experience physical discomfort associ-
ated with acid rebound when treatment is withdrawn for even
1 day, even if EGUS lesions do not recur during that timeframe. Fol-
lowing the precautionary principle, therefore, if horses are being
treated with omeprazole outside of competition then treatment on
the day of competition should be permitted on welfare grounds.
2. This recommendation (1) is consistent with fulfilment of the first
two, welfare-based key considerations of the ethical framework.
However, the third key consideration, that is, complying with gov-
erning body regulations cannot currently be reconciled with our
recommendation for all equine sports since some require that
omeprazole be withheld during competition. Revision of
6CAMPBELL and SYKES
regulations around the use of omeprazole during competition by
those governing bodies is, therefore, necessary to safeguard the
ethical use of horses in sport.
However, there are some caveats to these conclusions. All regula-
tors currently allow the use of omeprazole outside of competition. In
humans, in addition to hypergastrinaemia, the use of omeprazole can
cause such adverse effects as increased fracture risk, increased risk of
antimicrobial-associated diarrhoea, kidney injury and hypomagnesia.
26
To date, these adverse effects have not been demonstrated in horses.
A detailed discussion of the possible side effects of omeprazole treat-
ment in horses including effects on calcium digestibility and micro-
biota is beyond the scope of this article but is reviewed in Sykes.
16
Whilst it can be concluded that withholding omeprazole for longer
than 1 day in horses that are routinely being treated with it is ethically
undesirable for welfare reasons, the authors have confined our analy-
sis to the question of whether the use of omeprazole should be
allowed during competition and have not said anything about possible
health and thus welfare effects of the out-of-competition treatment
with omeprazole that all regulators of equine sport currently allow.
Furthermore, given the high incidence of EGUS in competition
horses
3
there remains an underlying ethical issue about whether
humans should be subjecting horses to management, training, and com-
petition regimens that result in poor health and welfare. That broader
topic is also outside the scope of this article, other than to comment
that evidence on how the incidence of EGUS in competition horses
compares to that in leisure horses should be used to inform welfare-
based decisions about how competition horses should be managed.
FUNDING INFORMATION
World Horse Welfare.
CONFLICT OF INTEREST STATEMENT
Madeleine L. H. Campbell declares no conflict of interest. Benjamin
W. Sykes has active consultancies with Kelato and Mayo Health,
who have products in the EGUS space. He has also, within the past
3 years, worked, for, or received funding from, the following compa-
nies with commercial interests in the EGUS space: Abbey Laborato-
ries, A-Vet, Equestra Australia, Health Food Symmetry, Hong Kong
Jockey Club, Norbrook UK, Salfarm Denmark, and Troy Australia.
None of the aforementioned companies had any input into this
manuscript.
AUTHOR CONTRIBUTIONS
Madeleine L. H. Campbell: Conceptualization; writing –original draft;
methodology; writing –review and editing. Benjamin W. Sykes:
Methodology; writing –original draft; writing –review and editing.
DATA INTEGRITY STATEMENT
No new data were created or analysed in this study.
ETHICAL ANIMAL RESEARCH
Not applicable.
INFORMED CONSENT
Not applicable.
DATA AVAILABILITY STATEMENT
Data sharing is not applicable to this article as no new data were cre-
ated or analysed in this study.
ORCID
Madeleine L. H. Campbell https://orcid.org/0000-0003-1123-5828
Benjamin W. Sykes https://orcid.org/0000-0002-0505-6228
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How to cite this article: Campbell MLH, Sykes BW. Should
the use of omeprazole be allowed during equestrian
competition? Equine Vet J. 2024. https://doi.org/10.1111/evj.
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