The essentials
- Pets normally need medication to treat Giardia — Your vet can give you the right prescription for your pet’s needs, but know it’s not uncommon for reinfection to happen after treatment. Be sure to monitor ongoing symptoms.
- Dog-to-human transmission can happen, but it’s rare — While zoonotic transmission of giardia is rare, it can happen. Handwashing and hygiene are important in lowering your risk.
- Giardia cysts aren’t always a concern — They can be found in many dogs’ poop, and may not be a concern if there are no other co-occurring symptoms (like diarrhea). However, if infectious symptoms are present, a vet visit is needed for further treatment and support.
Giardia in dogs—what is it and how dangerous can it be? Giardia is known by many as a parasite found in infected soil or water that can affect your pet, causing diarrhea and GI troubles. Unfortunately, infection isn’t all that uncommon. BioMed Central Veterinary Research found that giardia cysts were found in 36% of the study’s experimental group, pointing to a high occurrence rate in pets regardless of the presence of other symptoms.
TL;DR—if your pup enjoys adventuring outside or drinking from puddles, there’s a pretty high chance that they’ve encountered Giardia at some point.
Below, we’ll explore what giardia is, the types to watch for, and associated symptoms and fixes, helping you keep your dog as safe and healthy as possible.
What is giardia?
Giardia is a microscopic parasite that can wreak havoc on your dog’s GI tract in the event of a giardia infection. If left untreated, this single-celled parasite can lead to weight loss, watery diarrhea, and discomfort associated with intestinal infection. Support from your veterinarian is needed to address the clinical signs and help the infected animal, restoring your dog’s overall health from the inside out.
How do dogs get giardia?
Giardia can spread quickly in dog’s feces and pet-to-pet contact. It lives in the intestines of mammals and can be especially common anywhere that dogs, cats, and cattle frequent. This means that all feces-contaminated surfaces, soil, water and food are fair game when it comes to the spread of giardia in your pets.
Types of giardia that affect dogs
While there are many recognized types of giardia that can affect animals’ small intestine and a dog’s intestine, specifically, there are two main ones to watch for in puppies and adult dogs: giardia type C and type D.
Type C and D are also known as G. canis and are commonly associated with dogs. Many sources report that this type is rarely zoonotic. However, current diagnostic methods don’t test for the types—or assemblages—often. There are other types that can affect both dogs and humans (such as Giardia (G.) duodenalis) which are housed under the Giardia (G.) intestinalis classification “umbrella” and can cause symptoms.
⚠️ If you’re not sure what you’re dealing with, keep up with hot-water handwashing and environmental management to lower risk of transmission of giardia germs. People can still get sick, as giardia can be a zoonotic parasite. Keep your surrounding environment clean!
Symptoms of giardia in dogs
While every single case can vary, there are a few common symptoms of giardia to watch for.
- Loosening of your dog’s stool (either resulting in crumbly poops or watery diarrhea)
- Dehydration (often caused by the diarrhea)
- Nausea and abdominal pain
- Writhing, low growling, or other signs of discomfort
- Disorientation or dizziness
👉 Giardia symptoms can get serious very quickly. If you notice difficulty breathing, lethargy, seizures or rapid and severe weight loss, it’s time to go to the veterinary ER for follow-up testing. Be sure to see a vet at the start of the infection to assess and diagnose based on clinical symptoms.
How vets diagnose giardia in dogs
Giardia symptoms can vary by case—which is why seeking veterinary care and diagnosis is the most important thing to do if you’re worried about a possible parasitic infection.
Diagnosis can take place in many forms, including:
Stool exams
Signs of giardia assemblages can often be observed in the stool of an infected pet. Your vet can look for giardia spread by searching stool under a microscope. When they do this, they’ll be looking for cysts (infectious agents that can bring on infection weeks after they’re eliminated) and trophozoites—infectious agents which die quickly once passed in the poops.
⚠️ Be prepared to harvest stool samples over a few days’ time, as multiple “glimpses” might be needed to catch this highly unpleasant parasite. We say this for informational purposes only, though—talk to your pet first to determine what’s needed for a diagnosis of giardia.
Other types of testing
While many consider stool exams to be your best bet at diagnosing your dog’s internal systems, there are other options. These include:
- ELISA Immunosorbent assay: Your vet may use an FDA-approved SNAP test, which tests your dog’s blood for giardia.
- PCR testing: This test acts like a type of “DNA test” for giardia, allowing vets to see exactly what your pet is dealing with.
Treatment for giardia in dogs
Once diagnostic tests have been run, your vet will have a good idea about what type of giardia parasite you’re working with and how to help. Here are some common treatment options for subtypes of Giardia intestinalis:
Medications and recommended treatments
Medications may be recommended to limit the spread of giardia in your infected dog. The most common drugs to address giardia include fenbendazole and metronidazole, among other drugs. These medications may be covered by pet insurance if you have it.
🐕 Your vet can determine what other types of follow-up appointments and care are needed for moderate and severe cases of giardia, if any.
Role of dietary modification in treatment
Diet can be important in limiting the life cycle of giardia and preventing re-infection. It can also be an important part of treatment that can keep your dog comfortable, given the circumstances! Most vets might recommend feeding your dog a bland diet to soothe your pet’s gut, which may consist of their normal kibble, rice, chicken, or a specialty mix.
🥔 Before changing any parts of your dog’s diet to treat symptoms of illness, talk to your vet. They can help you meet your dog’s needs when it comes to diet and nutrition, even when they’re dealing with giardia organisms.
Prevention of giardia in dogs
Prevention is key to keeping your dog healthy year-round. Here are our top tips to keep Giardia duodenalis, Giardia lamblia and all other icky protozoan parasite friends at bay.
Environment clean-up
Pets are messy—and that mess can compound if you frequent dog parks, pet stores, and other places where your pet can pick up a “friend.” Healthy dogs need clean environments to come home to—which means pet parents should pay special attention to cleaning contaminated surfaces full of mud, water, and outside “icks.”
There should also be a clean water source available, whether it’s your faucet, water purifier, or another source you use. Food bowls and water bowls should be kept clean and filled with fresh water and snacks. Clean water should also be available to clean your pet after a day out with dog friends or any other outdoor adventures.
Need to clean? No problem. Pet-safe cleaners with quaternary ammonium compounds can be effective against giardia and related cysts. Chlorine bleach solution can also be effective treatment on hard surfaces. However, this can be caustic and harmful for pets—so if you use this, please rinse especially well afterward (and do so with a vet’s advice and oversight).
Regular vet checks
Routine vet visits are a good idea anyway, helping pet parents to keep their furry friends healthy and safe. Your vet can monitor for any signs or symptoms of infection and can suggest preventive measures to limit your dog’s exposure to giardia.
Long-term effects of giardia in dogs
We want to reiterate—giardia isn’t something that goes away on its own. If left untreated, it can lead to severe weight loss, electrolyte imbalance (which can cause heart failure and breathing difficulties), and death. Veterinary intervention is vital to helping your dog overcome giardia quickly.
Chronic giardia infection in dogs
Giardia can become chronic in some cases, resulting in excessively mucousy stools, foul-smelling diarrhea, vomiting, and bloody outputs. Your vet may choose to go with recurring antibiotic therapies to limit infectious spread, as well as supportive therapies to boost your dog’s quality of life.
Frequently asked questions
Can I touch my dog if he has giardia?
We know it can be tempting to give your pup all the love while they get through the illness. However, be careful if you do—as some types of giardia can be zoonotic (transfer from one species to another). Handwashing is key to stopping the spread.
How long are dogs contagious with giardia?
Unfortunately, dogs can shed the cysts for months—meaning that they can stick around in the environment for months. Our advice? If you’re dealing with an active infection, limit the “map” of where your dog can go in the house. Then, clean very vigorously and regularly until the vet clears them with a clean bill of health.
Can dogs pass giardia to humans by licking?
Yes. Any sort of contact with bodily fluids (even just a simple kiss on the cheek) can lead to the zoonotic spread of giardia.
What does zoonotic mean?
Zoonotic is a term that describes any sort of illness transmission between an animal and a human.
How can I decontaminate my yard from giardia?
Direct sunlight can kill giardia outside, including giardia in cyst form. If your dog makes messes inside, consider pet-safe solutions (like those listed above) and professional steam cleaning.
