What is Ollulanus infection?

Ollulanus tricuspis infection is a parasitic condition affecting the stomach of cats, with common symptoms including reduced appetite, vomiting, and weight loss. If you suspect infection, a veterinary examination is recommended to confirm the cause.

How does the vet check for Ollulanus infection?

The vet will review your pet’s history and perform a physical examination, supported by blood work, biochemistry, and imaging. Faecal samples or tissue may also be collected to confirm the pathogen or rule out other conditions.

How long does treatment usually take before improvement is seen?

This varies by severity; mild cases may improve within 48–72 hours, while more serious cases may require weeks to months of treatment and monitoring. Follow your vet’s recommended follow-up schedule.

What information can I record at home to help the vet?

Record the onset time, daily food intake, vomiting frequency and characteristics of the vomited material, stool colour and frequency, and take photos or videos for the vet to review.

How much do the tests and treatment usually cost?

Costs vary by clinic and region — ask your vet for an estimate before proceeding.

Disease Guide

Ollulanus Infection in Cats: Symptoms, Diagnosis & Care [2025]

Ollulanus tricuspis is a stomach parasite in cats that can cause chronic vomiting and gastritis; antiparasitic treatment is effective.

Take 1 minute to check the symptoms first

Last updated: 2026/01/06

Pethealthmap Editorial Team

Sources: AVMA, WSAVA, Veterinary Internal Medicine Society

When to See a Vet

Seek Emergency Care Immediately

•Complete refusal to eat for more than 24 hours
•Continuous vomiting for more than 24 hours with signs of dehydration
•Blood in stool or heavy diarrhea accompanied by lethargy

Schedule a Clinic Visit Soon (within 24–72 hours)

•Noticeably reduced appetite for more than one day but still eating small amounts
•Single or intermittent vomiting with otherwise normal alertness
•Significant weight loss or decreased activity within a short period

01What Symptoms Indicate a Problem?

Ollulanus infection in cats primarily causes gastrointestinal symptoms, most commonly reduced appetite, vomiting, and weight loss, often accompanied by changes in energy levels and abnormal bowel habits.

Noticeably reduced appetite or refusal to eat for more than one day
Repeated vomiting or vomiting lasting more than 24 hours
Significant weight loss over a short period
Decreased energy and reduced activity levels
Changes in bowel habits or abnormal stool characteristics (loose stools, bloody stool, etc.)
If symptoms persist or worsen, schedule a veterinary consultation as soon as possible

Seek emergency care immediately if you notice the following symptoms:

⚠️ Persistent vomiting with obvious signs of dehydration
⚠️ Blood in stool or profuse diarrhoea
⚠️ Extreme lethargy or inability to stand

02How to Assess Your Pet at Home: Key Observations and Emergency Warning Signs

Keeping a record of symptoms and changes at home helps your vet make a quicker assessment — note the timing, frequency, and capture photos or videos.

Note the date and time symptoms first appeared
Track appetite and actual food intake daily
Record the frequency, timing, and nature of vomiting episodes
Weigh your pet weekly and track weight trends
Monitor urination and bowel movement frequency, stool colour, and consistency
Use your phone to film or photograph vomiting, stools, or feeding behaviour
Bring your notes and media to the vet appointment to help with assessment

03How Will the Vet Make a Diagnosis? Common Diagnostic Tests

The vet will begin with a physical examination, then combine blood work, biochemistry panels, and imaging to identify the cause and rule out other conditions.

Physical examination

abdominal palpation to assess pain and overall condition

Blood count

evaluating infection response and anaemia

Biochemistry panel

assessing liver, kidney, and other organ function

Abdominal ultrasound

examining organ structure and checking for masses or fluid

Further tests if needed

tissue biopsy, faecal analysis, CT scan, or endoscopy

04Post-Diagnosis Treatment and Care: Medications, Diet, and Home Management

Treatment depends on diagnostic findings and typically includes supportive care alongside targeted therapy; follow-up appointments are needed to monitor recovery.

A medication and supportive care plan will be tailored to the diagnostic results
Dietary adjustments or a prescribed easily digestible therapeutic diet may be recommended
Continue monitoring food intake and vomiting at home throughout the treatment period
Attend follow-up visits as directed for blood work or imaging to assess recovery
If response to treatment is inadequate, referral to a specialist clinic may be considered
Keep notes of any changes during treatment and share them with your vet at follow-up

05What to Prepare Before the Vet Visit: Key Information to Help Your Vet

Write down when symptoms began and note any recent changes

List recent food types and any changes in feeding amounts

Record vomiting frequency, timing, and the characteristics of vomited material

Bring any recent blood test results or imaging reports if available

Prepare a list of current medications and supplements

Bring any video footage or photos of the symptoms for the vet to review

This content is for reference only and cannot replace a professional veterinary diagnosis. If your pet shows signs of illness, please seek veterinary care promptly.