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Onsior from £0.46
Please note that the delivery time may be longer than normal during this time due to the Royal Mail strike. If you require your pet goods more urgently we would recommend opting for DPD delivery

Standard UK Delivery from &pound2.99

Standard UK Delivery from £2.99

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Onsior Tablets are a non-steroidal anti-inflammatory (NSAID) medication for the treatment of pain and inflammation associated with chronic osteoarthritis in both dogs and cats. The active substance, Robenacoxib, works by blocking an enzyme that produces substances called prostaglandins, which are involved in pain and inflammation.

Onsior Tablets are presented as round beige to brown tablets in a variety of different strengths for accurate dosing.

Onsior Tablets for Dogs

Onsior Tablets for Dogs

From:£0.46 to… £1.13

Onsior Tablets are indicated for the treatment of pain and inflammation associated with chronic osteoarthritis in dogs. Onsior Tablets are a non-steroidal anti-inflammatory (NSAID)...[More info]

From:£0.46 to… £1.13
Onsior 6mg Tablets for Cats

Onsior 6mg Tablets for Cats


Onsior 6mg Tablets are indicated for the treatment of pain and inflammation associated with acute and chronic musculoskeletal disorders, and to reduce moderate pain associated with...[More info]


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 below).

Special warnings for each target species
In clinical studies, inadequate response to treatment was seen in 10–15% of the dogs.

Special precautions for use
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. 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 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.

Adverse reactions (frequency and seriousness)*
Gastrointestinal adverse events were reported very commonly, but most cases were mild and recovered without treatment. Vomiting and soft faeces were very common, decreased appetite and diarrhoea were common, and blood in the faeces was uncommon. In dogs treated up to 2 weeks no increases in liver enzyme activities were observed. However, with long-term treatment, increases in liver enzyme activities were common. 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. In very rare cases, lethargy may be observed. 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 or lactation
Do not use in pregnant or lactating dogs because the safety of robenacoxib has not been established during pregnancy and lactation or in dogs used for breeding.

Interaction with other medicinal products and other forms of interaction
Onsior must not be administered in conjunction with other NSAIDs. 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. 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. Do not administer with food since clinical trials demonstrated better efficacy of robenacoxib when administered without food or at least 30 minutes before or after a meal. Onsior tablets are flavoured and are taken voluntarily by most dogs. The tablets should not be divided or broken.
The recommended dose of robenacoxib is 1 mg/kg body weight with a range 1–2 mg/kg.
A clinical response is normally seen within a week. Treatment should be discontinued after 10 days if no clinical improvement is apparent.
For long-term treatment, once a clinical response has been observed, the dose of Onsior can be adjusted to the lowest effective individual dose reflecting that the degree of pain and inflammation associated with chronic osteoarthritis may vary over time. Regular monitoring should be undertaken by the veterinarian.

Overdose (symptoms, emergency procedures, antidotes), if necessary
In healthy young dogs aged 5–6 months, oral robenacoxib administered at high overdoses (4, 6 or 10 mg/kg/day for 6 months) did not produce any signs of toxicity, including no evidence of any gastrointestinal, kidney or liver toxicity and no effect on bleeding time. Robenacoxib also had no detrimental effects on cartilages or joints.
As with any NSAID, overdose may cause gastrointestinal, kidney, or liver toxicity in sensitive or compromised dogs. There is no specific antidote. Symptomatic, supportive therapy is recommended consisting of administration of gastrointestinal protective agents and infusion of isotonic saline.

Withdrawal period
Not applicable.