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POM-V Prescription Required Companion Animal

Onsior 20 mg Tablets for Dogs

Active ingredient: Robenacoxib

Form

Tablet

Species

Dogs

Manufacturer

Elanco GmbH

VMD MA No.

52127/5020

What it's used for

For the treatment of pain and inflammation associated with chronic osteoarthritis in dogs. For the treatment of pain and inflammation associated with soft...

Full indications, dosage and side effects ↓
View official SPC (PDF)

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Paying less for Robenacoxib

  1. 1

    Ask your vet for a written prescription

    They must provide one on request. Under the CMA Order the fee is capped at £21 from 2027.

  2. 2

    Fill it at a registered online retailer

    The CMA found online pharmacies 50–60% cheaper than practice dispensing on common medicines — typically £200–£300 a year.

Prescription required

Your vet must provide a written prescription on request. You can then purchase from any licensed online retailer.

Clinical information

Onsior 20 mg Tablets for Dogs — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 26 Mar 2026.

For the treatment of pain and inflammation associated with chronic
osteoarthritis in dogs.
For the treatment of pain and inflammation associated with soft tissue
surgery in dogs.

Issued: October 2023
AN: 02941/2022
Do not use in dogs suffering from gastrointestinal ulceration or with hepatic
disease.
Do not use concomitantly with corticosteroids or other non-steroidal anti-
inflammatory drugs (NSAIDs).
Do not use in case of hypersensitivity to the active substance or to any of the
excipients.
Do not use in pregnant and lactating animals (see section 4.7).
Dogs:
Very common
(>1 animal / 10 animals treated):
Digestive tract disorder
, Diarrhoea,
Vomiting
Common
(1 to 10 animals / 100 animals treated):
Elevated liver enzymes
Decreased appetite
Uncommon
(1 to 10 animals / 1,000 animals
treated):
Blood in the faecesVery rare
(< 1 animal / 10,000 animals treated,
including isolated reports):
Lethargy
Most cases were mild and recovered after treatment.
In dogs treated up to 2 weeks, there were no increases in liver enzyme
activities observed. However, with long-term treatment, increases in liver
enzyme activities were reported. In most cases there were no clinical signs
and the liver enzyme activities either stabilised or decreased with continued
treatment. Increases in liver enzyme activities associated with clinical signs of
anorexia, apathy or vomiting were uncommon.
Reporting adverse events is important. It allows continuous safety monitoring
of a veterinary medicinal product. Reports should be sent, preferably via a
veterinarian, to either the marketing authorisation holder or its local
representative or the national competent authority via the national reporting
system. See also the last section of the package leaflet for contact details.

Issued: October 2023
AN: 02941/2022
In clinical studies in dogs with osteoarthritis, inadequate response to
treatment was seen in 10–15% of the dogs.

i). Special precautions for use in animals
The safety of the veterinary medicinal product has not been established in
dogs weighing less than 2.5 kg or under 3 months of age.
For long term therapy, liver enzymes should be monitored at the start of
therapy, e.g. after 2, 4 and 8 weeks. Thereafter it is recommended to
continue regular monitoring, e.g. every 3–6 months. Therapy should be
discontinued if liver enzyme activities increase markedly or the dog shows
clinical signs such as anorexia, apathy or vomiting in combination with
elevated liver enzymes.
Use in dogs with impaired cardiac or renal function or dogs that are
dehydrated, hypovolaemic or hypotensive may involve additional risks. If use
cannot be avoided, these dogs require careful monitoring.
Use this product under strict veterinary monitoring in dogs with a risk of
gastrointestinal ulcers, or if the dog previously displayed intolerance to other
NSAIDs.
ii). Special precautions to be taken by the person administering the
veterinary medicinal product to animals
Wash hands after use of the veterinary medicinal product.

Issued: October 2023
AN: 02941/2022
In case of accidental ingestion, seek medical advice immediately and show
the package leaflet or the label to the physician. In small children, accidental
ingestion increases the risk for NSAID adverse effects.
For pregnant women, particularly near-term pregnant women, prolonged
dermal exposure increases the risk of premature closure of the ductus
arteriosus in the foetus.
Special precautions for the protection of the environment:
Not applicable.
iii). Other precautions
Not applicable.
This veterinary medicinal product must not be administered in conjunction
with other NSAIDs or glucocorticoids. Pre-treatment with other anti-
inflammatory medicines may result in additional or increased adverse effects
and accordingly a treatment-free period with such substances should be
observed for at least 24 hours before the commencement of treatment with
this veterinary medicinal product. The treatment-free period, however, should
take into account the pharmacokinetic properties of the products used
previously.
Concomitant treatment with medicines displaying action on renal flow, e.g.
diuretics or angiotensin-converting enzyme (ACE) inhibitors, should be
subject to clinical monitoring. In healthy dogs treated with and without the
diuretic furosemide, concomitant administration of this veterinary medicinal
product with the ACE inhibitor benazepril for 7 days was not associated with
any negative effects on urine aldosterone concentrations, plasma renin
activity or glomerular filtration rate. No safety data in the target population
and no efficacy data in general exist for the combined treatment of
robenacoxib and benazepril.
Concurrent administration of potentially nephrotoxic medicines should be
avoided as there might be an increased risk of renal toxicity.
Concurrent use of other active substances that have a high degree of protein
binding may compete with robenacoxib for binding and thus lead to toxic
effects.
Do not store above 25 °C.
Not applicable.
5.

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.

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