Fruit and Nut

Bah-Humbug! I was always surprised that there never appeared to be a health and safety risk assessment for ‘Cristingles’ at the children’s service on Christmas Eve. Who would normally give a child an orange covered in spikey cocktail sticks with sweets and raisins on and then put a lit candle on the top! Kids end up spiking themselves in the eye while trying to retrieve sweets or set either their own hair on fire or the hair of the girl in the pew in front. I’m a nervous wreck by the end of the service. But Christmas can be just as hazardous for our pets!

Pets are creatures of habit and while Christmas is a special time of the year for people it can be very stressful for pets. Visitors, parties, and decorations are all changes in routine which pets find difficult to manage. One of the biggest threats to pets at this time of year is from poisoning. At Christmas and New Year unusual and interesting things appear that dogs, and occasionally cats, investigate and which, if eaten, can poison them.

Poisonous threats can be divided in to different areas:  Christmas plants, festive foods & drinks, and antifreeze.

Christmas Plants are often used as decorations or are given as gifts and some can be poisonous. These include:

1)  Holly – The red berries on the holly plant can be poisonous if consumed in large amounts. Symptoms of holly poisoning include vomiting and diarrhoea, resulting in dehydration and electrolyte imbalance.

2)  Poinsettia – 
The poinsettia is a popular plant during the holiday season. The poinsettia sap is an irritant. If any part of the plant is ingested by a dog, cat, or other curious pet, the animal quickly shows signs of mouth irritation by shaking its head, hyper-salivating, or pawing at the head and mouth. The plant may also cause vomiting.

3)  Mistletoe – 
Mistletoe poisoning is rare but it does occur in dogs particularly over Christmas. If dogs eat large numbers of the berries it can cause serious poisoningand possibly even death. If dogs eat small numbers of berries it usually causes only an upset tummy.

4)  Christmas Cactus
 is a favorite Christmas gift and dogs are especially prone to poisoning because they like its taste and eat lots of it.

5)  Christmas Trees 
- Are considered to be mildly toxic. The fir tree oils can irritate the mouth and stomach, causing excessive drooling or vomiting. The tree needles are not easily digested either, possibly causing tummy upsets or bowel blockages.

6)  Amaryllis
 is a plant commonly given as a Christmas gift. It contains lycorine, a serious toxin to many animals and humans. Mild intoxication causes tummy upsets.

Festive foods tend to contain special luxury ingredients that are used more often and in larger quantities at this time of the year. Also food gifts which are often left as presents under the Christmas tree are sniffed out and eaten by dogs.

1)  Macadamia nuts
 – Ingestion of macadamia nuts by dogs has been associated with a nonfatal syndrome characterised by vomiting, weak and wobbly walking especially on the hind legs, muscle tremors, raised body temperature, and depression. Dogs are the only species in which signs have been reported.

One ounce (28g) of nuts can cause symptoms in a 20lb (9kg) dog within 12 hours; that’s about the size of a West Highland White Terrier. Dogs usually recover within 2 days.

2) Chocolate – contains a theobromine, a chemical similar to caffeine, which cannot be easily metabolised by animals so it builds up to dangerously toxic levels quickly in their body. The type of chocolate, the quantity eaten, and the size of your pet indicate how severe symptoms will be. Just one square of dark chocolate causes severe symptoms in a 10lb (4.5kg) dog, and 2 squares in a 20 lb (9kg) dog. Signs include vomiting and diarrhoea, irregular heartbeat, hyperactivity, muscle tremors, fitting, and possibly even death.

Good quality dark chocolate is 10 times more toxic than milk chocolate 

3)  Grapes and Raisins and fruit cake – are surprisingly poisonous to dogs, just a handful of either can be fatal. Initial symptoms include vomiting and diarrhoea which progress to symptoms of kidney failure within 24 hours. Urine becomes foamy and bloody, heartbeat and breathing become irregular. Death follows the later stages of kidney failure.

Dogs show symptoms following ingestion of about 1lb (460g) of grapes per 35lb (16kg) of body weight. Due to the severity of the signs and the potential for death, vets recommend aggressive treatment for any dogs suggested of having ingesting large amounts of grapes, raisins, or fruit cake. Treatment includes inducing vomiting, stomach lavage (stomach pumping), and administration of activated charcoal. This is followed by intravenous fluid therapy for at least 48 hours or as indicated based by the results of blood tests for kidney damage.

4)  Onions & Garlic – A chemical found in these foods, thiosulphate, causes the red blood cells in the circulation to rupture, resulting in anaemia. Baby food containing onion powder often kills puppies fed on it. Symptoms include difficulty breathing, vomiting, weakness, irregular heartbeat, and jaundice.

A large quantity of onions is required to cause symptoms in dogs. Moderate amounts cause no clinical symptoms but anaemia may be detected on blood tests. Small quantities seem to be well tolerated.

Cats are probably a little more sensitive to onion toxicity than dogs are.

Large amounts of garlic will produce similar toxicity problems in both dogs and cats.

5)  Avocado – A favorite as a Christmas Dinner starter with Prawn Marie Rose sauce.All products of the avocado plant are poisonous to dogs including guacamole dip made from it. It damages the heart muscle and other tissues, including the lungs. Symptoms of poisoning include difficulty breathing, irregular heartbeat, swollen abdomen, fluid build up around the heart, fitting, coma, and death.

Festive drinks tend to be alcoholic. Dogs, more than cats, may finish off beer, larger, and sweet cocktails. Pets are usually repelled by spirits because of the alcoholic fumes.

Alcohol – Depending on the size of the animal even a few laps of beer can cause intoxication. Symptoms include: disorientation, vomiting and diarrhea, fitting, coma, and death.

Alcohol poisoning doesn’t just occur as a result of drinking alcoholic drinks. Raw bread dough contains yeast which produces alcohol as it ferments. Dough may continue to rise following ingestion and as it expands it may cause rupture of the stomach or intestine on top of alcohol poisoning.

Seasonal Car Maintenance is essential with the current weather that we are experiencing. Many people will be topping up their antifreeze in their engine coolant. Antifreeze contains sweet-tasting ethylene glycol, among other dangerous chemicals. Its pleasant taste makes it likely to be drunk by pets and even small quantities can be fatal. Never leave antifreeze where pets can access it and be careful when and where old engine coolant is disposed of.

Ethylene glycol forms crystals in the kidneys and can cause kidney failure. Symptoms following ingestion include vomiting and diarrhoea, dilated pupils, depression, increased thirst, kidney failure, fitting, irregular heartbeat and breathing, coma, and death.


If you believe that your pet could have eaten, drunk, or chewed something poisonous call your vet and have the following information handy:

  • The name of the poison consumed.
  • How much the animal consumed.
  • How long ago the animal ate the poison.
  • The pet’s vital signs and symptoms.

Owners should not induce vomiting without instructions from a vet. Some substances do more damage to the gullet if they are vomited. Vomiting should never be induced in an animal that is in distress, fits, and unconscious or is having trouble breathing.

At Christmas time many owners seem to lose all their common sense and give their pets food to eat that they would never do at any other time of the year. A full roast dinner with all the trimmings! I used to hate being on-call on Boxing Day because I ended up picking up the pieces following the excesses of Christmas day!

Probably the worse thing that a dog could eat would be a dark chocolate bar containing raisins and macadamia nuts!

Happy Christmas!

David Chamberlain BVetMed., MRCVS.
Veterinary Consultant to PetSafe®

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