The standard treatment for disease in dogs is the antibiotic doxycycline PO @ 10mg/kg q24h for 30 days.
Rapid response is seen in limb and joint disease in most cases, although incomplete or transient resolution of signs occurs in a significant number of affected animals.
Due to the persistence of B. burgdorferi sensu lato, relapses can occur. Two different experimental studies of experimentally-infected dogs revealed that a 30-day course of therapy with amoxicillin, doxycycline, ceftriaxone and azithromycin failed to eliminate infection, though it did reduce the ability of investigators to isolate the organism from tissues. Longer courses of treatment may be necessary, particularly in dogs with nephropathy (kidney disease).
In cases of relapse, antibiotic treatment may be repeated as persistent infection is not the result of acquired antibiotic resistance. Prolonged antibiotic therapy (over 30 days) may be beneficial in certain cases with continuing disease signs.
Symptomatic therapy directed toward the affected organ system and clinicopathologic abnormalities is also important, especially in renal disease. In limb and joint disease, the use of NSAID (non-steroid anti-inflammatory drugs) concurrent with antibiotic therapy can lead to confusion over the source of clinical improvement and make diagnosis based on therapeutic response difficult.
Antibiotic treatment of clinically normal but seropositive dogs is controversial. Many seropositive dogs do not display evidence of clinical disease. However, because the course of infection can be prolonged, treating in the subclinical phase is viewed by some veterinarians as potentially beneficial in preventing the development of chronic disease.