Christmas Hazards from The Veterinary Poisons Information Service & The Blue Cross
With Christmas just days away, many of us have now put up the Christmas tree ready for the big day. Some pets may not be able to resist the temptation of chewing the branches on our decorative holiday plants.
The most common types of Christmas trees belong to the Pinaceae family, which include the Fir, Pine, and Spruce. They are all evergreen, resinous and monoecious plant species, with needle like leaves.
Christmas trees are considered to be of low toxicity. Most cases remain well or develop mild symptoms only. Ingestion may cause local ulceration, GI irritation (vomiting and diarrhoea), GI obstruction or physical injury (some needles can be very sharp). Contact dermatitis has also occurred in humans following chronic exposure, although there have been no reports of this in animals. A boxer developed haematemesis (vomiting blood), collapse and weakness after a large ingestion of pine tree bark. He was given cimetidine, oral fluids and sucralfate and made a full recovery within 24 hours.
If pets are seen chewing on the Christmas tree, they should be observed closely for any changes in behaviour. If the owner becomes concerned the practice is welcome to call the VPIS over the upcoming Christmas holidays for emergency advice.
During the festive season, artificial or fake snow may be used for window shop displays, events and family parties. The products generally contain synthetic acrylate polymers such as polyacrylate, which aid in the overall strength and resistance of the material. Some fake snow products also contain polyethylene emulsions. These products have recently been mislabelled as toxic on social media platforms.
Polyacrylate based products are generally regarded as having a low acute toxicity, but can cause GI irritation including vomiting, diarrhoea and abdominal tenderness. Most clinical effects are mild and self-limiting, and animals can be managed at home with oral fluids. If clinical signs persist, or the animal has ingested a very large quantity, it may be necessary to assess for any GI obstruction, although this is unlikely due to the flaky and particulate nature of the product.
Poylethylene is also considered of low toxicity. Systemic toxicity is not to be expected, given that it is chemically inert. Polyethylene fake snow did cause mild clinical signs in a 6kg dog, which included vomiting, hypersalivation and lethargy. However, the animal made a full recovery with supportive care and oral fluids.
The VPIS has not recorded any severe cases of poisoning reported to date, following ingestion of fake snow.
There are many plants traditionally associated with Christmas, bringing colour and joy to our homes and gardens. However, such plants may pose a risk to our beloved pets this time of year.
Euphorbia pulcherrima, known as poinsettia, is a popular ornamental houseplant at Christmas time. Although this plant has the reputation of being toxic, almost half of VPIS cases in cats and dogs remain asymptomatic. Vomiting, hypersalivation and depression may occur. Effects are expected to be rapid in onset, but are often mild and self-limiting. Supportive care is advised for symptomatic cases, which may include rehydration and an antiemetic.
The genusIlex comprises over 400 species. English holly (I. aquifolium) is used for decoration at Christmas, with its characteristic glossy, dark green leaves and bright red berries. All parts of the plant can be deemed toxic. The leaves and berries contain saponins which may cause local irritation. The leaves, berries and stems also contain cyanogenic glycosides, although clinical signs are largely due to the saponins. Such signs are expected within a few hours of ingestion. Gastrointestinal signs are common. Animals may also shake their heads and smack their lips in distress. Although gastric decontamination is not required, the throat should be checked for lodged leaves. Treatment is supportive.
Viscum album, European mistletoe, is also used as a festive decoration. The leaves and stems of the plant contain toxic proteins, however, most animals remain asymptomatic. Some animals may develop gastrointestinal irritation, with occasional reports of ataxia, hyperaesthesia and tremor. Gut decontamination is only advisable following ingestions of large quantities of plant material. Treatment is again supportive to control persistent GI disturbance and/or neurological signs.
The ivy that tends to be used in wreaths and decorations is Hedera helix (not Toxicodendron radicans, the American poison ivy). But the Hedera species can still cause a tummy upset when ingested. Where there is significant or prolonged skin contact, Hedera species can also cause both irritant and allergic contact dermatitis.
Vitis Vinifera: grapes, raisins and currants
Tis’ the season to be jolly and, of course, to eat Christmas cake, pudding and mince pies!
Vitis vinifera (common grape vine), produces a berry which is known as a grape. Grapes can be eaten fresh, processed to make wine or juice, or dried to produce; raisins, sultanas and currants. With Christmas round the corner, we are likely to have an increasing number of foodstuffs containing currants and raisins in our homes. This increases the risk of our pets getting hold of them.
VPIS recommends treatment for ingestion of any amount of grapes, raisins, sultanas and currants ingested in cats and dogs. Unfortunately, a toxic dose has not yet been established, as clinical signs have occurred at variable quantities ingested. There does not appear to be a dose-response relationship.
The main concern with the ingestion of grape products is renal failure. Clinical signs are expected to onset set within 24 hours. Vomiting occurs in the majority of cases. Bloody stools, tender abdomen, weakness and lethargy may also been seen. Renal failure can develop within 72 hours post ingestion.
Treatment must include gastric decontamination, aggressive intravenous fluid therapy and monitoring kidney function. Please see below some interesting cases of Christmas past:
A 7.1 kg border terrier ingested a substantial amount of Christmas cake. An x-ray revealed lots of material in the stomach. The dog presented vomiting. The renal parameters were normal within the first 24 hours post ingestion and the owner refused fluid therapy. However, the dog developed ataxia and weakness the next day and was brought back into practice. By 48 hours post ingestion, raised urea, raised creatinine and dehydration occurred. Despite intravenous fluids at twice maintenance rate for 36 hours, the dog was weak and frail and sadly did not respond to treatment. The owners elected for euthanasia.
A 32 kg labradoodle ingested part of a Christmas cake and, two days later, one mince pie. He suffered persistent vomiting for the two day duration. Following repeat doses of activated charcoal and intravenous fluids at twice maintenance rate over 48 hours, the dog made a full recovery.
Please do not hesitate to contact VPIS for treatment recommendations. Please be aware that our treatment protocols are updated regularly, as we are always receiving new cases and undergoing research.
The chemical theobromine, which is a bit like caffeine, is found in chocolate and is toxic to pets. Even small amounts can cause agitation, hyperexcitability, tremors, convulsions and problems with the heart. The darker the chocolate, the more potent levels of theobromine become – with baker’s chocolate the most dangerous. Chocolate should be avoided at all costs. But what do you do if your pet does eat chocolate? Even small amounts have the potential to make them feel sick, but veterinary treatment should be sought for any pet ingesting more than 20 mg/kg of theobromine – that’s equivalent to 3.5 g/kg of plain or dark chocolate and 14 g/kg milk chocolate. White chocolate does not contain enough theobromine to cause toxicity, but it can be fatty and pose a potential risk of pancreatitis. Avoid putting any chocolate on or under the Christmas tree, as the temptation might be too great for our four legged friends.
Onions (and garlic, leeks, shallots and chives)
Onions, garlic, leeks, shallots and chives all belong to the Allium species of plants and can cause toxicity, whether uncooked or cooked. Initially there can be vomiting and diarrhoea but the main effect is damage to red blood cells, resulting in anaemia. This may not be apparent for several days after ingestion.
Alcohol can have a similar effect in dogs as it does in their owners when drunk in excess. They can become wobbly and drowsy and in severe cases, there is a risk of low body temperature, low blood sugar and coma. Dogs may help themselves to any unattended alcohol left lying around over Christmas, so ensure it’s always out of their reach.
Macadamia nuts can cause lethargy, increased body temperature, tremor, lameness and stiffness in dogs.
If there is any food left over at Christmas, be careful to dispose of it well and keep it out of the reach of your four-legged friend. Not only may the food include ingredients toxic to dogs, mould in leftovers (including yoghurt, bread and cheese) can produce toxins that cause rapid onset convulsions in dogs.
A sugar-free sweetener called xylitol is often found in the sweets we consume over Christmas, as well as chewing gums, mouthwashes, toothpastes and supplements. It is poisonous to dogs and, although the amounts in different products vary, event one to two pieces of chewing gum can cause toxic effects in a small dog. It can induce the release of insulin in the body, resulting in low blood sugar and sometimes liver damage. Signs of poisoning can be rapid or delayed, and include vomiting, lethargy, convulsions and comas. The prognosis is good if the low blood sugar is treated quickly.
Silica gel comes in small sachets and is often found in the packaging of new shoes, handbags, cameras or electrical equipment which we unwrap over Christmas. Although it is labelled “Do not Eat” it is considered to be of low toxicity.
Decorations made of plastic, paper or foil are of low toxicity although may obstruct the stomach. Glass decorations could pose a risk if chewed or swallowed.
Wrapping or crepe paper
Ingestion may cause staining in the mouth which may look alarming, but the toxicity is considered to be low. But if your dog eats a large amount, it may cause an obstruction to the stomach.
Although candles, even scented ones, are considered to be of low toxicity, ingestion could potentially block the intestine or cause choking.
When eaten, potpourri can cause significant gastrointestinal effects in dogs. These may last several days even after the material has passed through the gut.
Nicotine is toxic to dogs, and cigarette butts are especially dangerous – so it’s important not to leave any ashtrays in reach of dogs over Christmas, or dropped on the floor where they may eat them. Nicotine replacement patches and e-cigarette refills can also pose a risk. Symptoms of poisoning include vomiting, excess saliva and hypertension.
If your worried that your pet has ingested any of the above during the festive season, please call us immediately on 01670 457271.