by ANDREW M. STREIBERby ANDREW M. STREIBER, DVM

Q:  I have a three month-old pup who has had all his regular visits to the veterinarian.  He’s up-to-date on vaccines, is on a proven monthly flea control, has had his feces tested multiple times, and been dewormed repeatedly.  The issue is that on his third fecal recheck he was found to be both positive on his giardia ELISA (enzime linked immunosorbent assay test) and to have a persistent, active giardia infection, all despite two treatments with Panacur, then Panacur & Flagyl (Metronidazole).  I’m both frustrated and concerned.  Do you have any other recommendations for treatment?

A:  Historically, I have encountered both extremes when treating giardia (a protozoa) in dogs.  Sometimes the infection clears immediately with the first treatment, and in other cases the infection persists despite multiple treatments.  Your situation sounds like the latter.

The treatment prescribed by your veterinarian was wholly appropriate despite it’s seeming ineffectiveness.  In rare cases such as yours, to eliminate the parasite from the patient’s G.I tract I take the following approach: either an additional, even longer (usually twice the norm) re-treatment with the same combination of Panacur & Flagyl, or an additional treatment for seven days using two different medications, Ronidazole and Azithromycin.  I have found both protocols to be effective in eliminating the giardia, as well as being tolerable for my patients.