Determination of an effective dose of eltenac and its comparison with that of flunixin meglumine in horses after experimentally induced carpitis.
OBJECTIVE
To titrate a clinically effective eltenac dosage (0.1, 0.5, and 1.0 mg/kg of body weight), compared with vehicle only, and to compare efficacy of the most effective eltenac dosage with that of 1.1 mg of flunixin meglumine/kg.


METHODS
40 healthy horses, ranked after model induction on the basis of lameness severity, were randomly assigned to 5 treatment groups, with 4 replicates of 10 horses each.


METHODS
On day -5, after surgical preparation of the left carpal region, 0.7 ml of Freund's complete adjuvant was injected into the intercarpal space. Horses were observed daily, from the day of carpitis induction to day 0, when stride length was used as the method of ranking horses for randomization to treatment assignment. Treatments were administered i.v. once daily for 3 consecutive days, starting on day 0. Prior to carpitis induction on day -5, and at time 0 (pretreatment), 2, 4, 12, 24, 36, 48, 60, 72, and 96 hours after treatment initiation, resting respiratory rate and pulse, rectal temperature, carpal circumference, carpal flexion angle, stride length, carpal hyperthermia, and signs of carpal pain were recorded.


RESULTS
Compared with the vehicle and 0.1 mg of eltenac/kg, 0.5 and 1.0 mg/kg caused statistically significant improvements (ie, reduction of carpal circumference, increase in carpal flexion angle, and increase in stride length of the affected limb), but values did not differ significantly between the 2 dosages. Thus, a dose-response plateau for eltenac was reached at 0.5 mg/kg. Comparison with flunixin meglumine at a dosage of 1.1 mg/kg did not indicate significant differences between the 2 treatment groups at the pivotal time of 96 hours for carpal circumference, carpal flexion angle, stride length, carpal hyperthermia, and signs of carpal pain. Adverse reactions were not observed.


CONCLUSIONS
Under conditions of this study, a dosage plateau for eltenac was determined (0.5 mg/kg) that was statistically equivalent to eltenac (1.0 mg/kg) and flunixin meglumine (1.1 mg/kg) in a 3-day i.v. dosing regimen.
Hamm
D
D
Research for Animal Health, Fayetteville, AR 72701, USA.
Turchi
P
P
Johnson
J C
JC
Lockwood
P W
PW
Thompson
K C
KC
Katz
T
T
D000704:Analysis of Variance; D000814:Aniline Compounds / Q000627:therapeutic use*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D002348:Carpal Bones; D003002:Clonixin / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D005552:Forelimb; D005620:Freund's Adjuvant; D005684:Gait; D006734:Horse Diseases; D006736:Horses; D007592:Joint Diseases / Q000188:drug therapy* / Q000503:physiopathology / Q000662:veterinary; D013583:Synovial Membrane; D013876:Thiophenes / Q000627:therapeutic use*
D000814:Aniline Compounds; D000894:Anti-Inflammatory Agents, Non-Steroidal; D013876:Thiophenes; C014558:flunixin meglumine; D005620:Freund's Adjuvant; C071200:eltenac; D003002:Clonixin