Module 5: Top 30 Veterinary-Only Prescription Drugs Part 1: Antimicrobial Agents and Nonsteroidal Anti-Inflammatory Drugs
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Cefovecin Summary
Brand Name: Convenia
Manufacturer: Zoetis Animal Health
Source: https://www.zoetisus.com/products/dogs/convenia/convenia.aspx
Available Dosage Forms
- Injection (lyophilized cefovecin sodium): 800 mg cefovecin per 10-mL multidose vial (80 mg/mL when reconstituted)
Dosage by Species
- Dogs: 8 mg/kg as a single subcutaneous injection; may be repeated in 7-14 days, not to exceed 2 injections total.
- Cats: 8 mg/kg as a single subcutaneous injection.
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
T ½ (hr) |
133 |
166 |
Vd (L/kg) |
0.122 |
0.09 |
Protein binding (%) |
98.5 |
99.5 |
Contraindications/Warnings
- Contraindicated in animals with β-lactam hypersensitivity.
- Do not administer orally.
- Do not use in animals younger than 4 months of age.
- Use with caution in renal impairment.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Carprofen
Doxycycline
Furosemide
Ketoconazole |
Cefovecin may displace these highly protein-bound drugs and increase the free fraction |
Storage/Stability
- Store the powder and the reconstituted product in the original carton, refrigerated at 36°F–46°F. Protect from light.
- Use entire vial contents within 56 days of reconstitution. Return the unused portion to the refrigerator in the original carton after each use.
- As with other cephalosporins, the color of the solution may vary from clear to amber at reconstitution and may darken over time. If product is stored as directed, solution color does not adversely affect potency.
Regulatory Considerations
- New Animal Drug Application (NADA) #141-285.
- ARCI (Racing Commissioners International) has not classified this drug.
Enrofloxacin Summary
Brand Name: Baytril
Manufacturer: Bayer Animal Health
Source: https://www.bayerdvm.com/3days/index.htm?ecid=dvm:baytril:avmacb:hdsdad:vnty::2663
Available Dosage Forms
- Oral film-coated tablets: 22.7 mg, 68 mg, 136 mg
- Oral beef-flavored chewable treat tablets: 22.7 mg, 68 mg, 136 mg (generic versions available)
- Injectable solution: 22.7 mg/mL, 100 mg/mL (for large animals only)
Compounded Formulations
- Enrofloxacin Compounded Oral Suspension, Veterinary, USP (20 mg/mL)
Dosage by Species
- Dogs: 5–20 mg/kg (2.27–9.07 mg/lb) orally as a single daily dose or two equally divided doses administered at 12-hour intervals.
- Cats: 5 mg/kg (2.27 mg/lb) orally as a single daily dose or two equally divided doses administered at 12-hour intervals.
- Horses: 5 to 7.5 mg/kg orally or 5 mg/kg by intravenous infusion once daily; not labeled for use in horses.
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
Horses |
Other |
T ½ (hr) |
4-5 |
6 |
5-10 |
Sheep: 1.5-4.5
Turtles: 18
Alligators: 55 |
Vd (L/kg) |
3-4 |
12-20 |
1.25 |
Sheep: 0.4
Cattle: 1.5 |
Protein binding (%) |
27 |
40 |
81.8 |
Cattle: 60 |
Contraindications/Warnings
- Contraindicated in animals with known hypersensitivity to fluoroquinolones.
- Avoid use of Baytril Taste Tabs or generic flavored tablets in dogs with known allergies or pork, or dogs undergoing a food allergy trial (the "beef" flavor is derived from pork products)
- Because of the risk of blindness in cats, do not exceed the recommended dosage. Consider using a different (safer) fluoroquinolone antibiotic in cats.
- Use in young animals is not recommended because of effects on developing cartilage. This includes in small and medium dog breeds 8 months of age or younger, large breeds 12 months or younger, and giant breeds 18 months or younger; also cats 12 months of age or younger.
Pregnancy Category
- Pregnancy Category C: use in pregnant or nursing mothers is not recommended because of effects on developing cartilage.
Drug Interactions
Drug(s) |
Interaction |
Antacids
Foods, supplements, or other products that contain calcium, iron, zinc, or aluminum (e.g., dairy products)
Sucralfate |
Chelation and inactivation of enrofloxacin |
Cyclosporine |
Fluoroquinolones may exacerbate the nephrotoxicity and reduce the metabolism of cyclosporine |
Glyburide |
Severe hypoglycemia |
Theophylline |
Blood levels increased 30%–50% by enrofloxacin |
Warfarin |
Increased warfarin blood levels |
Storage/Stability
- Store tablet dosage forms at room temperature. Protect from sunlight.
- Store injectable dosage forms at room temperature; refrigeration can cause precipitation of injectable solutions. Protect from sunlight.
- Store compounded enrofloxacin oral suspension in the refrigerator. Shake well before using.
Regulatory Considerations
- New Animal Drug Application (NADA) #140-141 (tablets), #140-913 (injection).
- Abbreviated New Animal Drug Application (ANADA) #200-551.
- ARCI (Racing Commissioners International) has not classified this drug.
Marbofloxacin Summary
Brand Name: Zeniquin
Manufacturer: Zoetis Animal Health, Inc.
Source: https://www.zoetisus.com/products/dogs/zeniquin.aspx
Available Dosage Forms
- Oral film-coated tablets: 25 mg, 50 mg, 100 mg, 200 mg
Compounded Formulations
- Marbofloxacin Compounded Oral Suspension, Veterinary, USP (25 mg/mL)
Dosage by Species
- Dogs: 2.75–5.5 mg/kg orally once daily.
- Cats: 2.75–5.5 mg/kg orally once daily.
- Horses: 2 mg/kg orally every 24 hours; not labeled for use in horses.
- Other: Ball pythons (Python regius), 10 mg/kg orally at least every 48 hours; not labeled for use in this species.
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
Horses |
T ½ (hr) |
9–12 |
13 |
7 |
Vd (L/kg) |
1.2–1.9 |
1.01 |
1.6 |
Protein binding (%) |
low |
low |
low |
Contraindications/Warnings
- Contraindicated in animals with known hypersensitivity to fluoroquinolones.
- Not for use in food-producing animals.
- Use in young animals is not recommended because of effects on developing cartilage. This includes in small and medium dog breeds 8 months of age or younger, large breeds 12 months or younger, and giant breeds 18 months or younger; also cats 12 months of age or younger.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Antacids
Foods, supplements, or other products that contain calcium, iron, zinc, or aluminum (e.g., dairy products)
Sucralfate |
Chelation and inactivation of marbofloxacin |
Cyclosporine |
Fluoroquinolones may exacerbate the nephrotoxicity and reduce the metabolism of cyclosporine |
Glyburide |
Severe hypoglycemia |
Theophylline |
Blood levels increased 30%–50% by marbofloxacin |
Warfarin |
Increased warfarin blood levels |
Storage/Stability
- Store tablets at room temperature. Protect from sunlight.
- Store compounded marbofloxacin oral suspension in the refrigerator. Shake well before using.
Regulatory Considerations
- New Animal Drug Application (NADA) #141-151.
- ARCI (Racing Commissioners International) has not classified this drug.
Pradofloxacin Summary
Brand Name: Veraflox
Manufacturer: Bayer Animal Health
Source: https://www.veraflox.com/en/about-veraflox/index.php
Available Dosage Forms
- Vanilla-flavored oral suspension 25 mg/mL in 15 mL and 30 mL bottles. Comes with container-specific dosing syringe calibrated in milliliters.
Dosage by Species
- Cats: 7.5 mg/kg orally every 24 hours.
- Dogs: 3–4.5 mg/kg orally every 24 hours; not labeled for use in dogs in the United States.
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
T ½ (hr) |
~7 |
5–10 |
Vd (L/kg) |
>2 |
4.5 |
Protein binding (%) |
35 |
30 |
Contraindications/Warnings
- Contraindicated in animals with known hypersensitivity to fluoroquinolones.
- Use in young cats (12 months or younger) is not recommended because of effects on developing cartilage.
- May cause bone marrow suppression in dogs; not approved for use in dogs in the United States.
- Because of effects on developing cartilage, pradofloxacin should not be used in small and medium dog breeds 8 months of age or younger, large breeds 12 months or younger, and giant breeds 18 months or younger; also cats 12 months of age or younger.
- Not for use in food-producing animals.
Pregnancy Category
- Pregnancy Category X, based on maternotoxic and fetotoxic effects seen in reproductive studies in rats and rabbits.
Drug Interactions
Drug(s) |
Interaction |
Antacids
Foods, supplements, or other products that contain calcium, iron, zinc, or aluminum (e.g., dairy products)
Sucralfate |
Chelation and inactivation of pradofloxacin |
Cyclosporine |
Fluoroquinolones may exacerbate the nephrotoxicity and reduce the metabolism of cyclosporine |
Glyburide |
Severe hypoglycemia |
Theophylline |
Blood levels increased 30%-50% by pradofloxacin |
Warfarin |
Increased warfarin blood levels |
Storage/Stability
- Store suspension at room temperature below 30°C (86°F).
- Discard 60 days after opening.
Regulatory Considerations
- New Animal Drug Application (NADA) #141-344.
Florfenicol Summary
Brand Names: NuFlor; Osurnia Otic Gel
Manufacturer: Merck Animal Health (NuFlor); Novartis Animal Health (Osurnia)
Source: https://www.valleyvet.com/swatches/242RX_L_vvs_000.jpg
Available Dosage Forms
- Injectable solution 300 mg/mL (NuFlor); each milliliter also contains n-methyl-2-pyrrolidone 250 mg, propylene glycol 150 mg, and polyethylene glycol qs
- Otic gel (Osurnia) in 1 mL single-dose tubes; each tube contains florfenicol 10 mg, terbinafine 10 mg, and betamethasone acetate 1 mg
Dosage by Species
- Cattle: 20 mg/kg by intramuscular injection in neck muscle only; repeat dose in 48 hours. Alternatively, a single 40 mg/kg dose may be administered by subcutaneous injection in the neck.
- Dogs: 1 mL (1 tube) otic gel per affected ear; repeat administration in 7 days.
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
Horses |
Other |
T ½ (hr) |
2 |
7.8 |
1.83 |
Turtles: 2-7.8
Fish: 4.25
Cattle: 3.2 |
Vd (L/kg) |
1.2 |
0.61 |
0.72 |
Turtles: 10-60 |
Protein binding (%) |
low |
low |
low |
Cattle: 13-19 |
Contraindications/Warnings
- Injectable solution should not be administered intravenously.
- Not for use in female dairy cattle 20 months of age or older or in calves to be processed for veal.
- Prescriptions for cattle must include a meat withdrawal time that is specific to the route of administration.
- Injectable solution should not be administered systemically in cats because of high propylene glycol concentration (may cause Heinz body anemia).
Pregnancy Category
- Effects of florfenicol on bovine reproductive performance, pregnancy, and lactation have not been determined. Not for use in animals intended for breeding purposes.
- Safe use of otic gel in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Macrolides |
Potentially compete at 50S ribosomal subunit and interfere with antimicrobial activity |
Storage/Stability
- Store florfenicol injectable solution at temperatures from 36°F to 86°F; refrigeration is not required.
- Injectable solution is light yellow to straw colored; color does not affect potency.
- Store otic gel under refrigerated conditions, between 36°F and 46°F; to facilitate comfort during administration, the product may be brought to room temperature and stored for up to 3 months.
Regulatory Considerations
- New Animal Drug Application (NADA) #141-063 (injection), #141-437 (otic gel).
Tilmicosin Summary
Brand Names: Micotil, Pulmotil AC, Pulmotil
Manufacturer: Elanco Animal Health
Source: https://www.valleyvet.com/ct_detail.html?pgguid=30e079f8-7b6a-11d5-a192-00b0d0204ae5
Available Dosage Forms
- Solution for injection (Micotil): 300 mg/mL
- Oral solution(Pulmotil AC): 50 mg/mL
- Feed additive (Pulmotil): 90.7 g/lb
Dosage by Species
- Cattle and sheep: 10-20 mg/kg as a single subcutaneous injection.
- Swine: Provide in drinking water at a concentration of 200 mg/mL
- Rabbits: 25 mg/kg as a single subcutaneous injection; repeat in 3 days if necessary.
(Alternative in rabbits: administer 5 mg/kg by subcutaneous injection; if tolerated, administered follow-up doses of 10 mg/kg on days 7 and 14.)
Pharmacokinetic Parameters
Parameter |
Cattle17 |
Sheep17 |
Swine |
T ½ (hr) |
29 |
34 |
25 |
Vd (L/kg) |
25 |
25 |
Not available |
Protein binding (%) |
low |
low |
low |
Contraindications/Warnings
- May cause sudden death following intravenous administration in many species, including humans, non-human primates, horses, camelids (alpacas and llamas), goats, and swine.
- May cause severe tissue necrosis following intramuscular injection.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Epinephrine |
Worsens cardiotoxicity in swine |
Storage/Stability
- Store at or below 86°F. Protect from direct sunlight.
Regulatory Considerations
- New Animal Drug Application (NADA) #140-929.
Tylosin Tartrate
Brand Name: Tylan
Manufacturer: Elanco Animal Health
Source: https://www.valleyvet.com/ct_detail.html?pgguid=7ef2885f-8f22-495d-a6c5-12069f4b5712
Available Dosage Forms
- Soluble powder: equivalent to 100 g tylosin base
- Injectable solution: 50 mg/mL, 200 mg/mL
Compounded Formulations
- Soluble powder may be used to prepare patient-specific capsules for use in small animals.
Dosage by Species
- Dogs: 25 mg/kg orally every 24 hours.
- Cats: 25 mg/kg orally every 24 hours.
- Ferrets: 10 mg/kg orally every 12 to 24 hours.
- Rabbits, gerbils, hamsters: 10 mg/kg by subcutaneous injection if indicated.
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
Cattle |
T ½ (hr) |
0.9 |
0.9 |
1 |
Vd (L/kg) |
1.7 |
1.7 |
1–2.3 |
Protein binding (%) |
low |
low |
low |
Contraindications/Warnings
- Contraindicated in animals with known hypersensitivity to tylosin or other macrolides.
- Do not administer to horses or ponies by any route.
- Do not administer orally in hindgut fermenters (e.g., rabbits, guinea pigs, hamsters) because of risk of dysbiosis and severe or fatal enterocolitis.
- Injectable solution contains 50% propylene glycol and should not be administered to cats (may cause Heinz body anemia).
Pregnancy Category
Drug Interactions
Drug(s) |
Interaction |
Fluconazole
Itraconazole
Ketoconazole
Voriconazole |
Increased blood levels of tylosin |
Chloramphenicol and other macrolides |
Competitive interference at 50S ribosomal subunit |
Cisapride |
Although significant in humans, cisapride blood levels do not appear to be affected by macrolides in dogs and cats |
Digoxin |
Tylosin may increase blood levels of digoxin |
Diltiazem, Verapamil |
May increase blood levels of tylosin |
Omeprazole |
May increase blood levels of tylosin |
Sucralfate |
Decreases absorption of tylosin |
Warfarin |
Tylosin may increase warfarin blood levels |
Storage/Stability
- Store soluble powder and injectable solution at controlled room temperature below 72°F, protected from direct sunlight.
- Store compounded capsules at room temperature in a moisture-resistant container.
- Solutions prepared from soluble powder should be discarded after 72 hours.
Regulatory Considerations
- New Animal Drug Application (NADA) #138-187 (soluble powder), #012-965 (injection).
- Available without a prescription until December 2016; beginning in 2017, tylosin will be a veterinary feed directive drug available by prescription only.
Carprofen Summary
Brand Name: Rimadyl
Manufacturer: Zoetis Animal Health; multiple generic manufacturers
Source: https://www.zoetisus.com/products/dogs/rimadyl-_carprofen_.aspx
Available Dosage Forms
- Caplets: 25 mg, 75 mg, 100 mg
- Chewable beef-flavored tablets: 25 mg, 75 mg, 100 mg
- Injectable solution: 50 mg/mL
Compounded Formulations
- Oral suspension 5 mg/mL (peer reviewed20)
Dosage by Species
- Dogs (oral): 4.4 mg/kg every 24 hours or 2.2 mg/kg every 12 hours
- Dogs (subcutaneous): 4.4 mg/kg administered preoperatively.
- Cats: 4 mg as a single subcutaneous or intravenous injection (European labeling).
- Horses (oral): 0.7 mg/kg every 24 hours for 4–9 days (European labeling).
- Horses (intravenous): 0.7 mg/kg as a single injection (European labeling).
- Ferrets (oral): 4 mg/kg every 24 hours.
- Ferrets (subcutaneous): 1–4 mg/kg as a single injection.
- Rabbits: 2–4 mg/kg by subcutaneous injection every 12–24 hours.
- Birds and reptiles: 1–4 mg/kg by subcutaneous injection every 24–72 hours.
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
Horses |
T ½ (hr) |
8 |
20 |
22 |
Vd (L/kg) |
0.12–0.22 |
9–49 (high interpatient variability) |
0.08–0.32 |
Protein binding (%) |
99 |
high |
high |
Contraindications/Warnings
- Do not use in animals with bleeding disorders due to the antiplatelet action of carprofen.
- Use with caution (if at all) in dogs that have pre-existing hepatic or renal insufficiency or are at increased risk of those problems. Rare cases of fatal hepatocellular necrosis have been reported.
- Use with caution (if at all) in cats because of possible nephrotoxicity.
- Avoid use of carprofen chewable tablets in pets that have known allergies to beef or are undergoing a food allergy trial.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Corticosteroids (prednisone, prednisolone, methylprednisolone, dexamethasone) |
Significantly increase risk of gastrointestinal toxicity; many veterinary pharmacologists consider concurrent administration of corticosteroids and NSAIDs to be an absolute contraindication requiring at least 1 week washout between drugs |
Digoxin |
Carprofen significantly increases digoxin levels |
Drugs that induce hepatic enzymes (phenobarbital, rifampin) |
Increased risk of hepatoxicity from carprofen metabolites |
Furosemide |
Carprofen reduces diuretic efficacy |
Highly protein-bound drugs (cefovecin, oral anticoagulants, sulfonamides) |
May displace or be displaced by carprofen |
Methotrexate |
Concurrent administration of NSAIDs significantly increases methotrexate levels |
Storage/Stability
- Store tablet dosage forms at controlled room temperature (≤86°F).
- Store unopened injectable solution in the refrigerator (36°F to 46°F). Once opened, store at room temperature (up to 77°F) for no more than 28 days.
- Store compounded carprofen oral suspension at room temperature or in the refrigerator for no more than 21 days. Shake well before using.
Regulatory Considerations
- New Animal Drug Application (NADA) #141-053 (caplets), #141-111 (chewable tablets), #141-199 (injectable solution).
- ARCI (Racing Commissioners International) has classified carprofen as a Class 4 substance.
Deracoxib Summary
Brand Name: Deramaxx
Manufacturer: Novartis Animal Health
Source: https://www.petflow.com/product/novartis/deramaxx-for-dogs
Available Dosage Forms
- Beef-flavored chewable tablets: 12 mg, 25 mg, 50 mg, 75 mg, 100 mg
Dosage by Species
- Dogs: 3–4 mg/kg orally every 24 hours for a maximum of 7 days (postoperative pain); 1–2 mg/kg orally every 24 hours as needed (osteoarthritis)
- Horses: 2 mg/kg orally every 12–24 hours; not approved for use in horses
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
Horses |
T ½ (hr) |
3 (labeled dose)
19 (>8 mg/kg) |
8 |
12.5 |
Vd (L/kg) |
1.5 |
NR* |
3.09 |
Protein binding (%) |
90 |
NR |
NR |
*NR = not reported |
Contraindications/Warnings
- Do not use in animals with bleeding disorders due to the antiplatelet action of carprofen.
- Do not use in animals that have pre-existing hepatic or renal insufficiency or are at increased risk of those problems.
- May accumulate or form toxic metabolites in cats with chronic use (not recommended for use in cats).
- Do not use deracoxib chewable tablets in dogs that have known allergies to beef or are undergoing a food allergy trial.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Corticosteroids (prednisone, prednisolone, methylprednisolone, dexamethasone) |
Significantly increase risk of gastrointestinal toxicity; many veterinary pharmacologists consider concurrent administration of corticosteroids and NSAIDs to be an absolute contraindication requiring at least 1 week washout between drugs |
Digoxin |
Deracoxib significantly increases digoxin levels |
Furosemide |
Deracoxib reduces diuretic efficacy |
Highly protein-bound drugs |
Deracoxib may displace or be displaced by other highly protein-bound drugs |
Methotrexate |
Concurrent administration of NSAIDs significantly increases methotrexate levels |
Storage/Stability
- Store at room temperature between 59°F and 86°F.
Regulatory Considerations
- New Animal Drug Application (NADA) #141-203.
- ARCI (Racing Commissioners International) has classified carprofen as a Class 4 substance.
Firocoxib Summary
Brand Names: Previcox, Equioxx
Manufacturer: Merial Animal Health
Source: http://www.previcox.com/Pages/ThePrevicoxDifference.aspx
Available Dosage Forms
- Chewable beef-flavored tablets (Previcox): 57 mg, 227 mg
- Equine oral paste (Equioxx): 0.82% w/w (8.2 mg firocoxib per gram of paste) in a 6.93 g oral syringe (total 56.8 mg firocoxib per syringe)
- Equine injection (Equioxx): 20 mg/mL in 25 mL vials
Dosage by Species
- Dogs: 5 mg/kg orally every 24 hours.
- Horses (oral): 0.1 mg/kg every 24 hours for up to 14 days.
- Horses (intravenous): 0.09 mg/kg every 24 hours for up to 9 days.
Pharmacokinetic Parameters
Parameter |
Dogs |
Horses |
T ½ (hr) |
6–8 |
30–40 |
Vd (L/kg) |
3 |
1.7–2.3 |
Protein binding (%) |
96 |
98 |
Contraindications/Warnings
- Do not use in animals with bleeding disorders due to the antiplatelet action of firocoxib.
- Do not use in animals with pre-existing gastrointestinal erosion.
- Do not use in animals with pre-existing hepatic, renal, or cardiovascular insufficiency.
- Use with caution and enhanced monitoring in animals that are dehydrated, hypovolemic, hypotensive, or receiving concomitant diuretic therapy.
- Avoid use of firocoxib chewable tablets in dogs that have known allergies to beef or are undergoing a food allergy trial.
- Do not use in conjunction with other NSAIDs (e.g., flunixin, phenylbutazone, aspirin) in horses.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Corticosteroids (prednisone, prednisolone, methylprednisolone, dexamethasone) |
Significantly increase risk of gastrointestinal toxicity; many veterinary pharmacologists consider concurrent administration of corticosteroids and NSAIDs to be an absolute contraindication requiring at least 1 week washout between drugs |
Digoxin |
Firocoxib significantly increases digoxin levels |
Drugs that induce hepatic enzymes (phenobarbital, rifampin) |
Increased risk of hepatoxicity from firocoxib metabolites |
Furosemide |
Firocoxib reduces diuretic efficacy |
Highly protein-bound drugs (cefovecin, oral anticoagulants, sulfonamides) |
May displace or be displaced by firocoxib |
Methotrexate |
Concurrent administration of NSAIDs significantly increases methotrexate levels |
Storage/Stability
- Store chewable tablets and equine oral paste at room temperature between 59°F and 86°F. Brief excursions up to 104°F for no more than 24 hours are permissible.
- Store equine injection at a controlled temperature between 68°F and 77°F. Brief excursions up to 86°F for no more than 24 hours are permissible.
Regulatory Considerations
- New Animal Drug Application (NADA) #141-230 (chewable tablets), #151-253 (equine paste), #151-313 (equine injection).
- ARCI (Racing Commissioners International) has classified firocoxib as a Class 4 substance.
Robenacoxib Summary
Brand Name: Onsior
Manufacturer: Novartis Animal Health
Source: http://us.onsior.com/en/about-onsior/pain_relief_dosing.aspx
Available Dosage Forms
- Yeast-flavored tablets: 6 mg
- Injectable solution: 20 mg/mL
Dosage by Species
- Cats (oral): 1 mg/kg every 24 hours, rounded up to the nearest whole tablet.
- Cats (subcutaneous): 2 mg/kg once daily for up to 3 days.
- Dogs: 1 mg/kg orally every 24 hours (United Kingdom labeling).
Pharmacokinetic Parameters
Parameter |
Dogs |
Cats |
T ½ (hr) |
1.2–1.7 |
1.7 |
Vd (L/kg) |
0.24 |
0.19 |
Protein binding (%) |
99 |
99 |
Contraindications/Warnings
- Do not use in animals with bleeding disorders due to the antiplatelet action of robenacoxib.
- Do not use in cats or dogs with pre-existing gastrointestinal erosion.
- Do not use in animals with pre-existing hepatic, renal, or cardiovascular insufficiency.
- Use with caution and enhanced monitoring in animals that are dehydrated, hypovolemic, hypotensive, or receiving concomitant diuretic therapy.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Corticosteroids (prednisone, prednisolone, methylprednisolone, dexamethasone) |
Significantly increase risk of gastrointestinal toxicity; many veterinary pharmacologists consider concurrent administration of corticosteroids and NSAIDs to be an absolute contraindication requiring at least 1 week washout between drugs |
Digoxin |
Robenacoxib significantly increases digoxin levels |
Drugs that induce hepatic enzymes (phenobarbital, rifampin) |
Increased risk of hepatoxicity from robenacoxib metabolites |
Furosemide |
Robenacoxib reduces diuretic efficacy |
Highly protein-bound drugs (cefovecin, oral anticoagulants, sulfonamides) |
May displace or be displaced by robenacoxib |
Methotrexate |
Concurrent administration of NSAIDs significantly increases methotrexate levels |
Nephrotoxic drugs (aminoglycosides, amphotericin B) |
May increase nephrotoxicity of robenacoxib |
Storage/Stability
- Store tablets at room temperature up to 86°F.
- Store injectable solution in the refrigerator (36°F–46°F). Discard 28 days after opening.
Regulatory Considerations
- New Animal Drug Application (NADA) #141-320 (yeast-flavored tablets), #141-443 (injectable solution).
- ARCI (Racing Commissioners International) has classified robenacoxib as a Class 4 substance.
Flunixin Meglumine Summary
Brand Name: Banamine
Manufacturer: Merck Animal Health
Source: https://www.google.com/save/me?bih=847&biw=1034&hl=en-US
Available Dosage Forms
- Injectable solution: 50 mg/mL (generic versions available)
- Oral paste: 1500 mg per 30 g syringe
Dosage by Species
- Horses: 0.5–1.1 mg/kg every 8 to 12 hours orally or by intravenous injection.
- Cattle: 1.1–2.2 mg/kg every 24 hours by intravenous injection for up to 3 days.
- Dogs: 0.5 mg/kg by intravenous injection (United Kingdom labeling).
Pharmacokinetic Parameters
Parameter |
Horses |
Cattle |
Dogs |
T ½ (hr) |
~4 |
4 |
3.7 |
Vd (L/kg) |
0.15 |
0.42 |
0.18 |
Protein binding (%) |
87 |
>99 |
92.2 |
Contraindications/Warnings
- Not for use in dairy or veal cattle.
- Do not use in bulls intended for breeding.
- Do not administer by intra-arterial injection. Intra-arterial administration can cause ataxia, incoordination, hyperventilation, agitation, and muscle weakness.
- Do not use in animals with pre-existing hepatic, renal, or cardiovascular insufficiency.
- Use with caution in animals that are dehydrated, hypovolemic, hypotensive, or receiving concomitant diuretic therapy.
- Do not allow products containing flunixin to reach ground water, water course, or sewage or drainage systems. Flunixin is structurally similar to nicotinic acid and harmful to aquatic organisms.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined. The manufacturer recommends against use in bulls intended for breeding purposes.
Drug Interactions
Drug(s) |
Interaction |
Corticosteroids (prednisone, prednisolone, methylprednisolone, dexamethasone) |
Significantly increase risk of gastrointestinal toxicity |
Digoxin |
Increases digoxin levels |
Enrofloxacin |
Significantly delays elimination (increases blood levels) of both drugs when administered concurrently with flunixin in dogs27 (effect in horses unknown) |
Furosemide |
Reduces diuretic efficacy |
Highly protein-bound drugs (cefovecin, oral anticoagulants, sulfonamides, phenylbutazone) |
May displace or be displaced by flunixin (cattle) |
Methotrexate |
Concurrent administration of NSAIDs significantly increases methotrexate levels |
Nephrotoxic drugs (aminoglycosides, amphotericin B) |
May increase nephrotoxicity of flunixin |
Other nonsteroidal anti-inflammatory drugs |
Significantly increase risk of gastrointestinal toxicity if administered concurrently with flunixin |
Storage/Stability
- Store flunixin dosage forms in the refrigerator or at controlled room temperature between 36°F and 86°F.
Regulatory Considerations
- New Animal Drug Application (NADA) #101-479 (injection), #137-409 (oral paste).
- Abbreviated New Animal Drug Application (ANADA) #200-124, #200-142, #200-387.
- ARCI (Racing Commissioners International) has classified flunixin as a Class 4 substance.
Phenylbutazone Summary
Brand Name: Multiple
Manufacturer: Multiple
Source: https://www.google.com/save/me?bih=847&biw=1034&hl=en-US
Available Dosage Forms
- Tablets: 100 mg, 200 mg, 1000 mg
- Oral powder: 10% w/w
- Injectable solution: 200 mg/mL
Compounded Formulations
- FDA-approved phenylbutazone products, not bulk chemical powder, should be used as the starting ingredient for compounded formulations in instances when phenylbutazone is not available in the desired dosage form and must be compounded.30
Dosage by Species
- Horses (oral): 2.2–4.4 mg/kg every 12 hours for 2–4 days, then reduced to lowest effective dose
- Horses (intravenous): 2.2–4.4 mg/kg every 12 hours, not to exceed 5 days
Pharmacokinetic Parameters
Parameter |
Horses |
Dogs |
T ½ (hr) |
3–5.6 |
2.5–6 |
Vd (L/kg) |
0.1 |
0.1 |
Protein binding (%) |
>99% |
>98% |
Contraindications/Warnings
- Use in dairy and food-producing animals is prohibited because of possible toxicity to humans.
- Do not administer by intra-arterial injection. Intra-arterial administration can cause severe CNS stimulation and seizures.
- Do not use in animals with pre-existing gastric ulceration or bleeding disorders.
- Use with caution (if at all) in animals with pre-existing hepatic, renal, or cardiovascular insufficiency.
Pregnancy Category
- Safe use in breeding or lactating animals has not been determined.
Drug Interactions
Drug(s) |
Interaction |
Corticosteroids (prednisone, prednisolone, methylprednisolone, dexamethasone) |
Significantly increase risk of gastrointestinal toxicity |
Furosemide |
Reduces diuretic efficacy |
Highly protein-bound drugs (cefovecin, oral anticoagulants, sulfonamides, flunixin) |
May displace or be displaced by phenylbutazone (cattle) |
Other nonsteroidal anti-inflammatory drugs |
May increase risk of gastric ulceration if administered with phenylbutazone |
Storage/Stability
- Store oral dosage forms at room temperature between 59°F and 86°F. Protect from sunlight. Close containers tightly when not in use.
- Store injectable solution in the refrigerator between 36°F and 46°F. Protect from light.
Regulatory Considerations
- New Animal Drug Application (NADA) #094-170 (tablets), #091-818 (powder), #011-575 (injection).
- ARCI (Racing Commissioners International) has classified phenylbutazone as a Class 4 substance.
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