Coccidia in Dogs: How to Spot the Signs

6 min read
6 min read

Updated - Sep 1st, 2022

Key Points

  • Coccidia are microscopic intestinal parasites.
  • The most common symptom of coccidia is diarrhea, but some cases are entirely asymptomatic.
  • A vet will perform a fecal flotation test to diagnose your dog with coccidia and give you a prescription for medication if a case is confirmed.
  • You can take preventative measures against coccidia by keeping your dog’s environment clean, promptly disposing of poop, and keeping up with yearly fecal tests at your dog’s annual wellness exam.

Coccidia are tiny, single-celled organisms that spend the majority of their life cycle in your dog’s intestines. These protozoan parasites latch onto and infect cells within your dog’s intestinal walls – causing your dog to develop a gastrointestinal tract infection called coccidiosis. 

Four species of coccidia can infect dogs. The isospora species is by far the most common species of coccidia and is the one vets and owners are usually referring to when speaking about coccidial infections.

While they may be invisible to the naked eye, these pesky protozoa can cause your pup some discomfort. But don’t panic – coccidia are fairly easy to diagnose and treat. Plus, you can help keep your furry friend parasite-free through preventive measures such as a yearly fecal exam.


Symptoms of coccidia can include:

Sometimes dogs experience cases of coccidia without any clinical signs. Unfortunately, if your dog has an asymptomatic case of coccidia, they can still spread the parasite and infect other dogs. Because of this, it’s a good idea to get your dog tested for coccidia regularly, regardless of whether or not they’re experiencing symptoms.

Puppies are at a higher risk of contracting coccidia than adult dogs, and because of their fragile immune systems, they’re more likely to develop severe complications such as anorexia or depression. That’s why vets usually recommend regular testing, especially for puppies.

Dogs who are immunocompromised are at higher risk of developing coccidia. It’s especially important to look out for your pet’s health during times of stress, like during a move to a new place or bringing home a new furry family member. 


Dogs can develop a coccidia infection by ingesting immature coccidia called coccidia oocysts. Infected dogs shed oocysts through their poop. These oocysts then contaminate the surrounding environment. Under certain conditions, the oocysts sporulate and become infectious. Most dogs ingest these sporulated oocysts by sniffing or licking feces or dirt.

Is your pup a fan of catching mice? Be careful. Dogs can also develop coccidia by ingesting infected prey, such as small rodents.    


A vet will diagnose your dog with coccidia by performing a fecal flotation test. Your vet will take a sample of your dog’s stool and examine it under a microscope for coccidia oocysts. If they find oocysts, your vet will diagnose your dog with coccidia.

Oocysts only occur in the isospora species, the most common species of coccidia. If a vet suspects your dog may be infected with a less common species, they may perform a blood test.


After they diagnose your dog, a vet will likely prescribe a medicine called sulfadimethoxine. Your vet will instruct you to administer the medication daily for up to two weeks. Sulfadimethoxine is taken orally, in the form of a tablet or liquid. Depending on the severity of their infection, some dogs require longer treatment periods than others.

If sulfadimethoxine is unsuccessful, other medications are available. Your vet will work with you to determine the right treatment for your dog.

If your puppy has severe symptoms, your vet may also suggest measures to address these, such as IV fluids, diet changes, or specific medicines to combat diarrhea and malnutrition. 

Recovery and care

While your dog is infected with coccidia, avoid areas with lots of other dogs to help prevent the parasite from spreading.

Mitigate your dog’s risk of reinfection by keeping their habitat clean. Coccidia are hearty, microscopic parasites that can live in an environment for months without you knowing. 

Use gloves and dispose of your dog’s feces immediately. If you allow feces to sit, coccidia oocysts may contaminate the area. You can also sanitize your home using antibacterial disinfectants or diluted chlorine bleach.


Dogs should receive a fecal exam yearly, at their regular vet checkup. During the fecal test, your vet will screen your dog for a series of parasites, including coccidia and a similar single-celled intestinal parasite, giardia. This test is crucial to catching asymptomatic cases before your dog unwittingly spreads coccidia to other dogs. 

It’s generally a good rule of thumb to stay away from potentially contaminated areas, especially if you’re the parent of a young puppy. Steer clear of dog parks where feces remain on the ground and avoid kennels that don’t practice good hygiene.

What to expect at the vet’s office

Before your visit, your vet will instruct you to collect a small stool sample from your dog. When you arrive at the office, they will perform a fecal flotation test by examining your dog’s stool sample under a microscope. If your vet sees oocysts within your dog’s sample, they’ll diagnose your dog with coccidia. 

After diagnosis, your vet will prescribe sulfadimethoxine and provide you with any further instructions for care and recovery. Your dog will have to return for a follow-up exam to determine if coccidia are still present after treatment.   

The bottom line

If your dog was exposed to coccidia or you notice any symptoms, make an appointment with your vet as soon as possible.. Coccidial infections are fairly simple to diagnose and treat, but should be treated promptly to avoid complications.

Keep up with preventative measures such as cleanliness, prompt poop disposal, and regular fecal exams at your dog’s annual check-up.


Can pet insurance cover coccidia?

Pumpkin dog insurance plans help you cover costs that arise from unexpected illness or injury – including vet visits and treatment if your dog contracts coccidia. 

Pumpkin also offers an optional preventative care package called Preventive Essentials to help you cover the costs of routine care. Though not insurance, this wellness add-on can reimburse you 100% for annual fecal exams necessary for coccidia prevention.  

Can I get coccidia from my dog?

Typically, no. The most common species of coccidia that infects dogs do not affect humans. One much rarer type of coccidia, called cryptosporidium, can be passed to humans.

Can coccidia pass between dogs and cats?

No. Coccidia are host-specific – meaning that in the vast majority of cases, they cannot be passed between different species of infected animals. One small exception to this rule is that your dog may become infected if they eat infected prey, such as a mouse.

Did you know

  • There are four types of coccidia species that can infect your dog, but the most common is a species called isospora.
  • Some infected dogs may not experience any symptoms at all, but can still pass coccidia to other dogs. That’s just one reason why regular testing is important.
  • Pumpkin Dog Insurance plans cover 90% of eligible vet visits, making it easier for you to provide your pet the best possible care if accidents and illnesses – such as unwelcome parasites – arise. Fetch a quote today!

Caitlin McQuade

Caitlin is a writer and the proud roommate of an adorable and elusive cat named Olive.
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