Signs of parasites in dogs can include diarrhoea, unexplained weight loss or poor growth, but these changes have other causes too, and some infected dogs look completely well.3, 7 This guide focuses on intestinal parasites, including worms and microscopic protozoa such as Giardia. Fleas, mites, heartworm and, on Australia's east coast, the paralysis tick need a different kind of assessment, which we cover briefly below. Your vet is always the person who diagnoses a parasite and decides on treatment; for daily gut and digestive support alongside that plan, many owners add Pure Majesty Pets Yeast Drops (A$47.00), a liquid with every amount per 1 mL published on the label.
Seek urgent veterinary care for collapse, breathing difficulty, unusually pale or blue gums, black, tarry stool, severe bloody diarrhoea, severe or prolonged vomiting, or a painful, swollen abdomen. Call your vet clinic or the nearest emergency vet straight away; never delay care for a supplement trial or for a "better" stool sample.8, 9
Changes worth reporting to your vet, without guessing the parasite
The useful question is what changed, how severe it is and what else happened around the same time. This checklist helps you talk to the clinic clearly; it is not a diagnostic score, and it can't tell you which worm or protozoan is involved.
| Change you notice | What it can and cannot tell you | Useful next step |
|---|---|---|
| Recurring loose stool, diarrhoea or mucus | Can occur with intestinal parasites. Food changes, inflammation and other causes also need to be considered.1, 4, 7 | Note when it started, how often it recurs and any other changes. Book a vet visit for unexplained, persistent signs. |
| Vomiting or a change in appetite | Non-specific; vomiting is not a defining sign of Giardia.1 | Describe how it has progressed and how severe it is. Severe or prolonged vomiting needs urgent care. |
| Weight loss, poor puppy growth or a pot-bellied look | Can occur with roundworms in young dogs; coccidiosis can also hold back puppy growth. Appearance alone does not identify the organism or how heavy the burden is.3, 5 | Bring your dog's age and dated weights in kg. A painful, swollen abdomen needs urgent care. |
| Weakness, unusually pale gums or black, tarry stool | May signal serious illness. Severe hookworm disease can affect young puppies before any eggs are passed in the stool.6 | Seek urgent care; don't take comfort from a negative result or wait to collect a better sample. |
If you've found something visible in the stool, our worms in dog poop guide lists the observations worth recording. A visible object and a symptom list still can't establish which treatment is right; for the bigger picture on roundworm, hookworm, whipworm, tapeworm, coccidia and Giardia, see our guide to intestinal parasites in dogs.
Not every Australian parasite lives in the gut: the paralysis tick
Australian owners have one external parasite that can't wait for a stool test. The paralysis tick (Ixodes holocyclus) lives along the eastern seaboard from North Queensland to Victoria. It is active year-round in the north and from spring to late autumn in the south, and RSPCA Queensland notes that numbers rise from October to March.10, 11
The signs look nothing like a worm problem: weakness or wobbliness in the hind legs, a change in the sound of the bark, retching or gagging, and drooling. The RSPCA Australia Knowledgebase recommends daily skin checks, and University of Queensland researchers found that 73% of ticks were attached on the head or neck, so start there and work back along the body, between the toes and under the collar.10, 12 Any of these signs is an emergency: go to a vet clinic straight away. No supplement, including ours, has any role here; ask your vet which registered tick product suits your dog and your postcode.
A dog can look well and still carry parasites
Roundworm infections often cause no obvious illness, light whipworm infections may cause no signs at all, and dogs carrying Giardia can appear perfectly healthy.3, 4, 1 Screening an apparently healthy dog and investigating a sick one answer different questions. Normal-looking stool or a past worming dose doesn't prove your dog is parasite-free; ask the clinic which check fits your dog's history, especially before boarding, after a move interstate or when a new puppy joins the household.
What is the test trying to answer?
Faecal flotation concentrates parasite stages so they can be seen under the microscope; antigen tests, including the Giardia ELISA, detect specific parasite components; PCR detects targeted genetic material. No single method answers every parasite question equally well. Giardia shedding can be intermittent, so your vet may ask for combined testing or repeat samples collected over several days.2 In summer, keep a collected sample cool and get it to the clinic quickly; ask the clinic how they want it stored.
Two Giardia results that need context
Finding an organism, explaining an illness and checking the response to treatment are three separate questions. These two limits apply to Giardia specifically; they are not rules for every positive parasite test.
| Result and context | What it does not establish on its own | Question for your vet |
|---|---|---|
| Giardia-positive PCR with digestive signs | Sensitive PCR can detect a small Giardia burden that may be incidental or secondary to another gastrointestinal cause. A positive result does not automatically explain every symptom.1 | Does this finding explain the illness, or should another cause be investigated as well? |
| Giardia-positive ELISA or PCR after treatment | These methods can stay positive for variable periods. This result alone does not establish reinfection or treatment failure.2 | Is this the right follow-up method, given the treatment history and current signs? |
A positive finding still needs your vet's interpretation. It isn't a reason to ignore the result, assume it's harmless leftover material or automatically repeat a medication.
Prepare a record that matches the clinical question
- Changes: when signs started and how they've progressed, stool or vomiting observations, appetite, energy, age and dated weight (kg) or growth changes.
- History: adoption or travel dates and places (including interstate trips), boarding, doggy day care or dog-park contact, contact with faeces and scavenging.
- Actual results: the organism as reported, the test method and the collection date. Mark any missing details as unknown.
- Prior care: medication or product packaging, the dates given and whether symptoms changed afterwards.
Let the clinic set the sample instructions and when to recheck. Persistent signs deserve another assessment for ongoing infection, reinfection or a different cause; your record doesn't decide which applies, and it doesn't establish resistance or justify another dose on its own.
Once a worm has been identified, our best dewormer for dogs guide can help you discuss treatment coverage with your vet. Giardia is a protozoan, not a worm, so a worming product isn't automatically appropriate for every intestinal parasite. In Australia, veterinary medicines are regulated by the APVMA; treatment is your vet's call, and a supplement is never a replacement for it.
Supporting your dog's gut alongside the vet plan
A parasite episode, and the diarrhoea that often comes with it, can leave your dog's digestion unsettled for a while. Once your vet has a plan in place, daily nutritional support can help maintain digestive tolerance and comfort. For more on that recovery phase, see our dog gut health guide.
Pure Majesty Pets Yeast Drops are an oral liquid with 19 named actives, roughly 292 mg of active support per 1 mL, every amount published. Its gut–skin blend is the part most relevant here:
| Ingredient | Amount per 1 mL | Role in the formula |
|---|---|---|
| L-glutamine | 25 mg | Gut–skin axis blend; supports the gut lining |
| Saccharomyces boulardii postbiotic | 20 mg | Stabilised cell-wall fraction, not a live-CFU probiotic |
| Oregano, standardised to 70% carvacrol | 4 mg (~2.8 mg carvacrol) | Botanical; a supportive amount, not a pharmaceutical one |
| Botanical base | Included in the 292 mg | Pumpkin, slippery elm, marshmallow root, DGL licorice, aloe inner leaf, ginger |
Give 1 mL with food, dosed to your dog's weight as shown on the label; shake well first. The drops are made in North America in a GMP facility, with a certificate of analysis (COA) for every batch. They support digestive tolerance; they do not kill, treat or clear worms, Giardia or ticks, and they never replace an indicated antiparasitic medicine. Free worldwide shipping — ships to Australia with duties and GST prepaid (DDP), nothing to pay on delivery. Check suitability with your vet first, particularly for a sick, pregnant or nursing dog, a young puppy or a dog on medication. If you'd also like a live-culture option, compare our guide to probiotics for dogs with diarrhoea.
Frequently Asked Questions
What are the signs of intestinal parasites in dogs?
Diarrhoea, unexplained weight loss, poor growth, a pot-bellied look in puppies and other changes can prompt a vet check, but they are not a parasite diagnosis on their own. Severe illness needs urgent care, and some infected dogs show no signs at all.
Can a dog have parasites without symptoms?
Yes. Roundworms, light whipworm infections and Giardia can all occur without obvious illness. Your vet chooses screening or diagnostic tests based on your dog's circumstances; normal-looking stool is not proof of clearance.
Does a positive Giardia test explain every episode of diarrhoea?
No. Sensitive PCR may detect a small Giardia burden that is incidental or secondary to another gastrointestinal cause. Your vet needs to interpret the finding alongside your dog's signs and consider other causes where appropriate.
Why might a Giardia test stay positive after treatment?
Giardia ELISA and PCR can stay positive for variable periods after treatment. A positive result alone does not establish reinfection or treatment failure; ask your vet which follow-up method fits the case.
Is a wobbly back end a sign of worms?
Not usually. In eastern Australia, hind-leg weakness, a changed bark, retching or drooling can be signs of paralysis tick poisoning, which is an emergency. Get your dog to a vet clinic immediately.
Can I order Pure Majesty Pets Yeast Drops in Australia?
Yes. A bottle is A$47.00, with bundle savings on the product page. Free worldwide shipping — ships to Australia with duties and GST prepaid (DDP), nothing to pay on delivery. Use them as daily support alongside, never instead of, your vet's parasite plan.
Turn the signs into a useful next step
When you notice signs of parasites in dogs, write down the changes, check for ticks if you live on the east coast, and book the right assessment with your vet. Once the vet plan is under way, support your dog's digestion every day with Pure Majesty Pets Yeast Drops: A$47.00 a bottle, every amount on the label, a COA for every batch, and delivered to your door with nothing extra to pay.
Sources
- Lucy J. Robertson. Merck Veterinary Manual. Giardiasis in Animals. 2026.
- Companion Animal Parasite Council. Giardia: dog guidance. Updated 3 August 2026.
- Andrew S. Peregrine. Merck Veterinary Manual. Roundworms in Small Animals. 2026.
- Andrew S. Peregrine. Merck Veterinary Manual. Whipworms in Small Animals. 2026.
- Anthony Andrews. Merck Veterinary Manual. Coccidiosis of Cats and Dogs. 2026.
- Andrew S. Peregrine. Merck Veterinary Manual. Hookworms in Small Animals. 2026.
- Cornell Riney Canine Health Center. Diarrhea. Undated.
- Cornell University Hospital for Animals. Emergency and Critical Care. Undated.
- Merck Veterinary Manual. When to See a Veterinarian. Undated.
- RSPCA Australia Knowledgebase. How can I protect my dog or cat from tick paralysis?
- RSPCA Queensland. What you need to know about ticks.
- University of Queensland. Paralysis ticks prefer heads and necks of pets. October 2025.
This article is for informational purposes and is not veterinary advice. Talk to your veterinarian before starting any supplement, especially if your dog is pregnant, nursing, on medication, or has a diagnosed condition.