Indications for use, specifying the target species
For the treatment of pain and inflammation associated with acute or chronic musculo-skeletal disorders in cats.
For the reduction of moderate pain and inflammation associated with orthopaedic surgery in cats.
Do not use in cats suffering from gastrointestinal ulceration.
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 below)
Special warnings for each target species
Special precautions for use
Special precautions for use in animals
The safety of the veterinary medicinal product has not been established in cats weighing less than 2.5 kg or under 4 months of age.
Use in cats with impaired cardiac, renal or hepatic function or in cats that are dehydrated, hypovolaemic or hypotensive may involve additional risks. If use cannot be avoided, these cats require careful monitoring.
Response to long-term treatment should be monitored at regular intervals by a veterinary surgeon. Clinical field studies showed that robenacoxib was well-tolerated by most cat for up to 12 weeks.
Use this veterinary medicinal product under strict veterinary monitoring in cats with a risk of gastrointestinal ulcers, or if the cat previously displayed intolerance to other NSAIDs.
Special precautions to be taken by the person administering the veterinary medicinal product to animals
Wash hands after use of the veterinary medicinal product.
In small children, accidental ingestion increases the risk for NSAID adverse effects. In case of accidental ingestion, seek medical advice immediately and show the package leaflet or the label to the physician.
In pregnant women, particularly near term pregnant women, prolonged dermal exposure increases the risk for premature closure of the ductus arteriosus in the foetus.
Adverse reactions (frequency and seriousness)
Mild and transient diarrhoea, soft faeces or vomiting were commonly reported in clinical trials with treatment up to 6 days. In very rare cases, lethargy may be observed. Vomiting was very commonly reported, and anorexia, diarrhoea, lethargy and inappropriate defecation were commonly reported in field studies with treatment up to 12 weeks in cats with chronic musculo-skeletal disorder, with similar frequencies in the Onsior and placebo treated cats.
The frequency of adverse reactions is defined using the following convention:
- very common (more than 1 in 10 animals displaying adverse reaction(s) during the course of one treatment)
- common (more than 1 but less than 10 animals in 100 animals)
- uncommon (more than 1 but less than 10 animals in 1,000 animals)
- rare (more than 1 but less than 10 animals in 10,000 animals)
- very rare (less than 1 animal in 10,000 animals, including isolated reports).
Use during pregnancy, lactation or lay
Do not use in pregnant and lactating animals because the safety of robenacoxib has not been established during pregnancy and lactation or in cats used for breeding.
Interaction with other medicinal products and other forms of interaction
Onsior must not be administered in conjunction with other NSAIDs or glucocorticosteroids. 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 Onsior. 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 cats treated with or without the diuretic furosemide, concomitant administration of Onsior with the ACE inhibitor benazepril for 7 days was not associated with any negative effects on plasma 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.
As anaesthetics may affect renal perfusion, the use of parenteral fluid therapy during surgery should be considered to decrease potential renal complications when using NSAIDs peri-operatively.
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.
Amounts to be administered and administration route
For oral use.
Give either without food or with a small amount of food. Onsior tablets are easy to administer and well accepted by most cats. The tablets should not be divided or broken. 4
The recommended dose of robenacoxib is 1 mg/kg body weight with a range 1–2.4 mg/kg. The following number of tablets should be given once daily at the same time every day:
Body weight (kg)
Number of tablets
2.5 to 6
6 to 12
Acute musculoskeletal disorders treat: for up to 6 days.
Chronic musculo-skeletal disorders: Duration of treatment should be decided on an individual basis.Please refer to Special Precautions For Use.
A clinical response is normally seen within 3-6 weeks. Treatment should be discontinued after 6 weeks if no clinical improvement is apparent.
Orthopaedic surgery: Give as a single oral treatment prior to orthopaedic surgery. Premedication should only be carried out in combination with butorphanol-analgesia. The tablet(s) should be administered without food at least 30 minutes prior to surgery.
After surgery, once daily treatment may be continued for up to two further days. If necessary, additional analgesic treatment with opioids is recommended.
The interchangeable use of Onsior tablets and Onsior solution for injection has been tested in a target animal safety study and was shown to be well tolerated by cats.
For cats, Onsior solution for injection or tablets may be used interchangeably in accordance with the indications and directions of use approved for each pharmaceutical form. Treatment should not exceed one dose (either tablet or injection) per day. Please note that the recommended doses for the two formulations are different.
Overdose (symptoms, emergency procedures, antidotes), if necessary
In healthy young cats aged 7–8 months, oral robenacoxib administered at high overdoses (4, 12 or 20 mg/kg/day for 6 weeks) did not produce any signs of toxicity, including no evidence of any gastrointestinal, kidney or liver toxicity and no effect on bleeding time.
In healthy young cats aged 7- 8 months, oral robenacoxib (Onsior tablets) administered at overdoses of up to 5 times the maximum recommended dose (2.4 mg, 7.2 mg, 12 mg robenacoxib/kg bodyweight ) for 6 months was well tolerated. A reduction in body weight gain was observed in treated animals. In the high dose group kidney weights were decreased and sporadically associated with renal tubular degeneration/ regeneration but not correlated with evidence of renal dysfunction on clinical pathology parameters.
The interchangeable use of Onsior tablets and Onsior solution for injection in 4-month old cats at overdoses of up to 3 times the maximum recommended dose (2.4 mg, 4.8 mg, 7.2 mg robenacoxib/kg orally and 2.0 mg, 4.0 mg and 6.0 mg robenacoxib/kg subcutaneously) resulted in a dose-dependent increase of sporadic oedema at the injection site and minimal to mild subacute/chronic inflammation of the subcutaneous tissue. A dose-dependent increase in the QT interval, a decreased heart rate and corresponding increased respiratory rate were observed in laboratory studies. No relevant effects on body weight, bleeding time or evidence of any gastrointestinal, kidney or liver toxicity were observed.
In overdose studies conducted in cats, there was a dose-dependent increase in the QT interval. The biological relevance of increased QT intervals outside of normal variations observed following overdose of robenacoxib is unknown. No changes in the QT interval were observed after single intravenous administration of 2 or 4 mg/kg robenacoxib to anaesthetised healthy cats.
As with any NSAID, overdose may cause gastrointestinal, kidney, or liver toxicity in sensitive or compromised cats. There is no specific antidote. Symptomatic supportive therapy is recommended and should consist of administration of gastrointestinal protective agents and infusion of isotonic saline.