Hi Kendall,

Thanks for your question.

This is a very typical scenario. Giardia is a parasite that is really stubborn in our dogs and it’s not uncommon to do multiple treatments to try to get rid of it.

One of the reasons why Giardia is difficult to get rid of is that our dogs can auto-infect themselves. What this means is that when they shed the Giardia cysts, which are essentially like eggs that can stick to the hairs around their butt, or other places in the home or yard, like their bedding, carpets, and elimination areas in the yard. Then if they walk through these areas and lick their paws or groom themselves, they run the risk of ingesting these cysts and becoming infected again. For this reason it is really important to practice good husbandry in the home and in the yard. Whenever you do a treatment make sure you clean everything by doing laundry, restricting access to areas of the yard, mopping the floors, and wipe their paws after walks. One of the most important things you can do to prevent auto-infection is to use a soapy solution and scrub your dog’s butt area on the first day and last day of treatment. This is a critical process that I have everybody do even on the first round of treatment.

You are using the right medications to get rid of this infection, but they still often fail on their own. Try to implement the things that I’ve already discussed so far and hopefully they will help. Lastly, there are cases where I know that the Giardia exists but I stop the treatment. I now only treat it 2 to 3 times and then I only continue if the treatment failed. If the dog does not have clinical symptoms, such as diarrhea, lethargy, and they often don’t with Giardia, I won’t treat it and let mother nature take its course. I may even let them go through a winter season so it kills cysts outside. I will then re-check the fecal test in the spring and see if it’s still present. Keep in mind that if your dog is healthy and happy and you’ve had multiple treatment failures like you’ve experienced here, there’s nothing wrong with letting some time pass and hoping the dog’s immune system naturally deals with this problem on its own and then re-checking to see if it still exists. Even some of the top parasitologists in Canada suggests this as a strategy for Giardia because it can be so stubborn and refractory to treatment. I would recommend you speak to your veterinarian about some of these strategies to come up with a treatment plan that’s best for your dog.

I hope this helps.

Dr. Clayton Greenway