Amantadine in a multimodal analgesic regimen for alleviation of refractory osteoarthritis pain in dogs.
BACKGROUND
Nonsteroidal anti-inflammatory drugs (NSAIDs) do not always provide sufficient pain relief in dogs with osteoarthritis (OA).


OBJECTIVE
The use of amantadine in addition to NSAID therapy will provide improved pain relief when compared with the use of nonsteroidal analgesics alone in naturally occurring OA in dogs.


METHODS
Thirty-one client-owned dogs with pelvic limb lameness despite the administration of an NSAID.


METHODS
The study was randomized, blinded, and placebo controlled with parallel groups (days 21-42). On day 0, analgesic medications were discontinued. On day 7, all dogs received meloxicam for 5 weeks. On day 21, all dogs received amantadine (3-5 mg/kg once daily per os) or placebo for 21 days, in addition to receiving meloxicam. Assessments were performed before the study and on days 7, 21, and 42. Primary outcome measures were blinded owner assessments of activity using client-specific outcome measures (CSOM) on days 0, 7, 21, and 42. Data were analyzed by a mixed model approach.


RESULTS
For CSOM activity, there was a significant time by treatment effect (P=.009). On the basis of the planned post hoc t-tests of postrandomization means, there was a significant difference between treatment groups on day 42 (P=.030), with the amantadine group being more active.


CONCLUSIONS
In dogs with osteoarthritic pain refractory to an NSAID, physical activity is improved by the addition of amantadine. Amantadine might be a useful adjunct therapy for the clinical management of canine osteoarthritic pain.
Lascelles
B D X
BD
Comparative Pain and Orthopedic Research Laboratories, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA. Duncan_Lascelles@ncsu.edu
Gaynor
J S
JS
Smith
E S
ES
Roe
S C
SC
Marcellin-Little
D J
DJ
Davidson
G
G
Boland
E
E
Carr
J
J
D000547:Amantadine / Q000008:administration & dosage / Q000627:therapeutic use*; D018712:Analgesics, Non-Narcotic / Q000627:therapeutic use*; D000818:Animals; D004283:Dog Diseases / Q000188:drug therapy* / Q000209:etiology; D004285:Dogs; D004311:Double-Blind Method; D004334:Drug Administration Schedule / Q000662:veterinary; D005260:Female; D008297:Male; D010003:Osteoarthritis / Q000150:complications / Q000188:drug therapy / Q000662:veterinary*; D010146:Pain / Q000188:drug therapy / Q000209:etiology / Q000662:veterinary*
D018712:Analgesics, Non-Narcotic; D000547:Amantadine