Most of the limping dogs that are referred to our practice have received at least one course of nonsteroidal anti-inflammatory drug (NSAID) therapy at some point in their histories. In our practice, we also often prescribe rest and NSAIDs for dogs that have acute lameness without an obvious surgical solution. However, we frequently evaluate cases in which the first course of NSAID therapy and rest didn't work, and the referring veterinarians had increased the NSAID dose or prescribed a different NSAID without an appropriate washout period, which can range from three to 14 days.

Increasing NSAID doses or switching to a different NSAID can result in marked side effects, with potentially fatal complications. In our practice, duodenal perforations have been associated with all NSAIDs on the market, and such cases are documented in the literature as well.^1-3 These cases often involved multiple factors, many of which are still not completely understood. While it is true that a range of individual responses to NSAIDs are seen in people and that varied responses may hold true for dogs as well, the most common reason NSAIDs fail to work is that an underlying problem still needs to be addressed.

Lameness may be neurologic in origin (e.g. a neuropathy or brachial plexus tumor) or related to musculoskeletal neoplasia or to structural problems in the joint that need surgical attention (e.g. early partial cruciate tears without instability, shoulder instability). These problems can be subtle, requiring advanced imaging techniques for an accurate diagnosis. So if a dog's lameness fails to respond to a few weeks of NSAID therapy, referral may be a better option than reaching for another NSAID.

Julie D. Smith, DVM, DACVS

REFERENCES

1. Lascelles BD, Blikslager AT, Fox SM, et al. Gastrointestinal tract perforation in dogs treated with a selective cyclooxygenase-2 inhibitor: 29 cases (2002-2003). J Am Vet Med Assoc 2005;227:1112-1117.

2. Runk A, Kyles AE, Downs MO. Duodenal perforation in a cat following the administration of nonsteroidal anti-inflammatory medication. J Am Anim Hosp Assoc 1999;35:52-55.

3. Duerr FM, Carr AP, Bebchuk TN, et al. Challenging diagnosis—icterus associated with a single perforating duodenal ulcer after long-term nonsteroidal antiinflammatory drug administration in a dog. Can Vet J 2004;45:507-510.