Onsior® 6 mg Tablets for Cats for Short‑Term Pain Relief

What Onsior® Is and How It Works

Onsior® (robenacoxib) is a nonsteroidal anti‑inflammatory drug (NSAID) for cats. It is used for the control of postoperative pain and inflammation after orthopedic and soft‑tissue surgery. Veterinarians may also use it for short‑term relief of musculoskeletal pain in cats. Onsior 6 mg tablets for cats are the labeled oral form most clinics dispense.

CanadianInsulin is a prescription referral service. Prescriptions are verified with your clinic, and orders are filled by licensed Canadian pharmacies. We work with licensed and vetted partner pharmacies to supply authentic brand medications, with a broad selection and value‑focused pricing.

Robenacoxib is a COX‑2 selective NSAID. It reduces production of prostaglandins that drive pain and swelling, while sparing COX‑1 pathways more than traditional NSAIDs. This selectivity supports comfort, but NSAID risks still apply, especially to the gastrointestinal tract, kidneys, and liver in sensitive cats.

The tablet strength for feline use is 6 mg. The usual cadence is once daily for a short course, often three days. An injectable formulation exists for veterinary use around surgery. The flavored tablets are small and designed for easy administration by cat owners under veterinary guidance.

Dosage and Usage

• Typical indication: short‑term control of postoperative or acute musculoskeletal pain and inflammation in cats.
• Usual oral dose: 1 mg/kg once daily for up to 3 days, as directed by a veterinarian.
• Weight bands commonly used with 6 mg tablets: 2.5–6.0 kg (one 6 mg tablet); >6.0–12.0 kg (two 6 mg tablets).
• Do not split or crush the tablets. Give whole. The tablets are palatable.
• Give at about the same time each day. Cats may take it with or without a small amount of food.
• If a dose is missed and it is still the same day, give when remembered. If the next day has started, skip the missed dose. Do not double up.
• Duration is typically three days for postoperative use. Longer courses require veterinary oversight.
• Do not combine with other NSAIDs (including aspirin) or corticosteroids. Allow a suitable washout period if switching agents.
• Use caution with diuretics, ACE inhibitors, or nephrotoxic drugs. Discuss concurrent therapies with the prescribing veterinarian.
• Safety has not been established in cats under 4 months of age, under 2.5 kg (5.5 lb), breeding, pregnant, or lactating cats.

• Storage: keep tablets at 20–25°C (68–77°F). Short excursions 15–30°C (59–86°F) are acceptable.
• Protect from moisture and light. Keep tablets in the original blister until use. Close any secondary container tightly.
• Do not freeze. Do not store in a humid bathroom.
• Keep out of reach of children and other pets.
• Travel: carry tablets in the original labeled packaging. Use a small travel case to prevent crushing.
• Avoid leaving medicine in a hot car. If traveling in heat, place the pack in an insulated pouch away from direct ice packs.
• When flying, keep tablets in carry‑on luggage to prevent loss or extreme temperatures.

Benefits and Savings

Robenacoxib provides targeted anti‑inflammatory action and analgesia for cats after surgery and during acute flare‑ups. Once‑daily dosing for a short course keeps routines simple. The small, flavored 6 mg tablets support easy administration. Multimodal use with other classes (such as opioids) around surgery is common under veterinary care.

Many customers save 60–80% vs typical U.S. prices. If you plan to buy Onsior for cats alongside other pet prescriptions, combining items in one shipment may reduce overall per‑order costs.

Side Effects and Safety

• Common side effects may include vomiting, soft stool or diarrhea, decreased appetite, and lethargy.
• Less common effects can include increased drinking or urination, constipation, or injection‑related reactions if given by a veterinarian as an injection.
• Lab changes sometimes noted with NSAIDs include kidney or liver enzyme elevations.
• Stop treatment and contact a veterinarian if there is persistent vomiting, black or bloody stool, jaundice, severe lethargy, or loss of appetite.

Serious risks are uncommon but can include gastrointestinal ulceration or bleeding, kidney injury, and liver adverse events. Risk increases with dehydration, pre‑existing kidney or liver disease, concurrent steroids or other NSAIDs, or in very young or senior cats with comorbidities. Do not use in cats under 4 months, under 2.5 kg, breeding, pregnant, or lactating cats. Avoid combining with corticosteroids, other NSAIDs, or drugs that reduce kidney blood flow without veterinary supervision.

Hypersensitivity to robenacoxib or prior NSAID intolerance is a contraindication. Provide your veterinarian with a full medication and health history before starting therapy.

Onset Time

Analgesic effects generally begin within 30–60 minutes of an oral dose. Many cats show improved comfort within the first dosing day. Peak effect often occurs 1–3 hours after dosing. Each dose typically provides about 24 hours of relief, so steady response is seen over the three‑day course when dosing is consistent.

Compare With Alternatives

Meloxicam (brand often known as Metacam) is another NSAID used in cats. Robenacoxib is more COX‑2 selective, while meloxicam is less selective. Labeling and approved durations differ by country and formulation. Cats with prior NSAID stomach or kidney concerns may need an alternative plan under veterinary guidance.

Buprenorphine is an opioid analgesic often used with an NSAID after surgery. It helps with breakthrough pain but can cause sedation or dysphoria in some cats. It is commonly administered by a veterinarian or dispensed for buccal dosing at home.

Gabapentin is a non‑NSAID option used for neuropathic components of pain, pre‑visit sedation, or as a multimodal adjunct. It can cause drowsiness or ataxia. It does not replace an anti‑inflammatory like robenacoxib for inflammatory pain, but it can complement it.

An injectable robenacoxib formulation is used by veterinarians around surgery. Tablets provide convenient at‑home dosing for the short recovery period that follows.

Combination Therapy

• Perioperative plans often pair an NSAID with an opioid such as buprenorphine for stronger early analgesia.
• Gabapentin may be added for multimodal control, especially with neuropathic features or severe discomfort.
• Do not combine robenacoxib with other NSAIDs or corticosteroids. Allow appropriate washout periods between agents.
• Ensure good hydration. Cats with kidney or gastrointestinal disease need extra caution and veterinary monitoring.

Patient Suitability and Cost‑Saving Tips

Cats needing short‑term postoperative pain relief are typical candidates when a veterinarian deems an NSAID appropriate. Cats with acute soft‑tissue or musculoskeletal pain may benefit from a brief course. Suitability depends on age, weight, baseline lab values, and other medicines.

Onsior may not be appropriate for cats with known NSAID intolerance, active gastrointestinal disease, dehydration, kidney or liver impairment, clotting disorders, or for use in pregnant or lactating queens. Discuss risks and monitoring plans with the prescribing clinic.

To manage costs, consider ordering the prescribed quantity of 6 mg tablets in one shipment. If a veterinarian anticipates repeated short courses for procedures in multiple pets, combining items can reduce per‑order overhead. Multi‑month supplies should only be requested when clinically appropriate. You can set simple reorder reminders so refills are not missed when needed.

Authoritative Sources

Elanco manufacturer information for Onsior (robenacoxib) for cats

Health Canada Drug Product Database: Onsior 6 mg tablets (robenacoxib)

FDA FOI Summary: Onsior (robenacoxib) tablets for cats

Order Onsior® from CanadianInsulin: add to cart, upload your prescription, and we ship with prompt, express, cold‑chain handling.

This page is educational and does not replace advice from a licensed veterinarian. Always consult a veterinary professional for diagnosis, treatment options, and individualized dosing decisions.