A Christmas special


‘Twas the day before Christmas

And all round the house,

The dog chased the cat

Who chased her toy mouse.

Their owner watched on with a fond, kindly eye,

Arranging Christmas lilies,

Nibbling Christmas mince pies.

Hanging chocolates on the tree,

Then chopping onions for the BBQ at 3.

The first guest (from Gribbles) arrived, gave a cry

Be careful with those, Lest your fur-kids might die!

After the year we’re having, most of us will be hoping for some “down-time” and a few treats over the Christmas period, but some holiday traditions can be hazardous to pets, so here are some seasonal reminders:

Christmas lilies (Lilium regale):

There are many different types of lily, but only members of the genera Lilium (true lilies) and Hemerocallis  (day lilies) have been definitively associated with renal failure in cats. Dogs do not appear to be at similar risk. Some cats appear to have a “fatal attraction” to lilies. The toxic principle is thought to be a mixture of steroidal glycoalkaloids. All parts of the plant are toxic, including the pollen.

Christmas mince pies:

All of the Christmas fruity treats—pies, pudding and cake all contain raisins. Consumption of raisins or grapes is associated with acute renal failure in dogs and possibly in cats. The toxic principle is unclear but appears to be in the flesh, not the seed. The toxic dose seems highly variable. Some dogs may consume substantial amounts without developing clinical signs, but it is safest to assume that any amount may be potentially toxic.

For both these toxicities, clinical signs develop in two to several hours and may include vomiting, lethargy, anorexia, abdominal pain, hypersalivation, ataxia, tremors, occasional seizures and polydipsia which may progress to adipisa. Oliguric to anuric renal failure may develop in 24- 72 hours and death in 3-5 days.

Urinalysis and biochemistry may show isosthenuria, proteinuria, glucosuria, granular casts, increased urea, creatinine, amylase, lipase, potassium, phosphate, calcium and ALT. Prognosis is favourable with early intervention such as induction of vomiting (if safe), gastric lavage, activated charcoal and IV fluids (if not anuric). Peritoneal dialysis has been successful in some cases but once anuria develops prognosis is poor.


Chocolate contains variable concentrations of theobromine, a methylated xanthine alkaloid, which can cause CNS stimulation, increased rate and force of myocardial contraction, increased gastric secretion, smooth muscle relaxation and diuresis. Clinical signs occur within 6-12 hours and may include vomiting, diarrhoea, polyuria, restlessness, tachycardia, tachypnoea, hyperthermia, cardiac arrhythmia, seizure, coma and death. Clinical pathology is non-specific but may include haemoconcentration, low USG, low blood glucose, hypokalaemia.

Treatment involves induced emesis (if early) or gastric lavage, controlling seizures and arrhythmias, gut protectants and supportive care.


All members of the Allium species (including onions and garlic) or sausages or meat patties containing these, have sulphur containing oxidants that can increase Heinz bodies and methemoglobin in red blood cells, with subsequent (often >72 hours later) haemolysis, anaemia and haemoglobinuric nephrosis. Urine is sometimes red/brown.

There is no specific antidote but early and appropriate supportive care is an important factor in prognosis.


Finally, don’t forget the Christmas ham – one of my colleagues recalls treating a case of salt toxicity when a dog scoffed one of those down! 

Let’s hope all of our animals can avoid these holiday hazards and that we all have a safe and relaxing festive season.