Hyperosmolar Hyperglycaemic State in Dogs & Cats: Symptoms, Blood Sugar Testing & Treatment [2025]
Hyperosmolar hyperglycaemic state is a serious complication of diabetes, characterised by extremely high blood glucose without significant ketone production. It requires urgent hospitalisation with fluid therapy and insulin management.
When to See a Vet
Immediate veterinary care needed (emergency)
- •Persistent lethargy with sluggish response to the environment
- •Frequent vomiting and unable to keep food or water down
- •Poor skin elasticity with obvious signs of dehydration
Schedule a clinic visit as soon as possible (within 24-72 hours)
- •Appetite is clearly decreased and remains lower than usual
- •Water intake is significantly increased, with frequent active seeking of water
- •Noticeable weight loss over a short period or looking thin
01What symptoms indicate something is wrong?
Hyperosmolar hyperglycaemia commonly causes systemic weakness and metabolic dehydration, presenting clinically as lethargy, changes in appetite and markedly increased water intake.
- Dullness, lethargy or noticeably reduced activity levels
- Obvious weakness, easy fatigue or decreased mobility
- Repeated vomiting or persistent reduced appetite or refusal to eat
- Rapid weight loss over a short period, visibly thin appearance
- Increased urination or more frequent night-time urination (often accompanied by increased thirst)
- Significantly increased water intake with obvious signs of excessive thirst
- If any of the above occur, arrange an endocrinology specialist assessment as soon as possible
Seek emergency care immediately if you notice the following symptoms:
- ⚠️ Reduced level of consciousness or persistent lethargy
- ⚠️ Repeated vomiting with inability to eat or drink
- ⚠️ Obvious dehydration with poor skin turgor
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02How do you assess the situation at home? Key observations and criteria for seeking emergency care
Observing and recording specific changes at home can help the vet quickly assess the condition and determine the treatment direction.
- Record mental state and activity level changes (onset time and severity)
- Note the number of vomiting episodes, characteristics of vomit and the times they occurred
- Weigh your pet at the same time each day and track the trend
- Record the daily number of urinations and total water intake (estimate number of cups)
- Note changes in appetite, types of food and amount consumed
- Record time of onset, any exposure history or possible triggers (medications, environment)
- Compile records and bring them to share with the endocrinology specialist at the appointment
03How will the vet diagnose? Common diagnostic tests
At the clinic, the focus will be on physical examination and laboratory tests, with imaging added if necessary for further evaluation and to rule out concurrent disease.
Physical examination
assess body condition, degree of dehydration and level of consciousness
Point-of-care blood glucose measurement to determine the extent and fluctuation of hyperglycaemia
Complete blood count and biochemistry panel to evaluate organ function and electrolytes
Urinalysis to assess glucosuria, urine specific gravity and signs of infection
Imaging (X-ray, ultrasound or CT) if needed to rule out concurrent conditions
Recommended to visit a specialist hospital equipped with blood glucose monitoring and imaging
04How is it treated and managed after diagnosis? Medication, dietary adjustments and care guide
Treatment focuses on correcting dehydration and electrolyte imbalances, controlling blood glucose, and continuing follow-up and adjustment of the treatment plan after discharge.
- Intravenous fluid therapy is often required in the acute phase to correct dehydration and electrolyte imbalances
- Insulin therapy and blood glucose monitoring carried out under veterinary supervision
- Adjust diet formulation and feeding method as directed, with guidance on home management
- Regular follow-up appointments to monitor blood glucose, blood biochemistry and clinical improvement
- Recording blood glucose or urine glucose at home can help the vet fine-tune the treatment plan
- Hospitalisation or specialist review may be needed if the condition is unstable or complications arise
05What should you prepare before the vet visit? Key information to help the vet quickly identify the cause
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.