Anti-freeze Poisoning
By Ginny Lovrich
As winter months approach, so to does the incidence of accidental poisoning of cats and dogs from vehicle anti-freeze. Unfortunately both the smell and taste of this commonly used product are generally appealing to pets, but even small amounts can be deadly if ingested.
Anti-freeze poisoning is not the exclusive domain of the colder South Island regions where pet owners may use the liquid in their household plumbing to prevent freezing pipes as well as in their cars. Many cars have some component of anti-freeze in their radiators and unbeknown to pet owners their animals may stop to lick or drink this sweet tasting liquid from a leak or a puddle of inadequately disposed-of fluid. Similarly pets can drink from toilet bowls where antifreeze is used in homes.
The harmful ingredient in antifreeze is ethylene glycol, an extremely toxic chemical. Even the smallest amount of this liquid can be fatal to a cat or dog. (It is also extremely hazardous to children.) For a medium sized dog, ingestion of about three to four tablespoons is toxic. For cats, as little as one to two teaspoons can be damaging, even fatal.
So when you’re handling any anti-freeze this season, remember to carefully dispose of all the waste coolant. If there are any spills flush the area with water, ensuring that it is well diluted. And remember also that this is not just a winter risk - poisoning can happen anytime, particularly when a car boils over or when a hose leaks, releasing the antifreeze.
Often owners will be unaware of any poisoning. It may occur with pets that freely roam or to those that are restricted to garage areas, or possibly areas without adequate fresh water to drink.
So what are the signs to watch for? Symptoms of antifreeze poisoning include a drunken appearance including staggering, lack of co-ordination, and apparent disorientation, vomiting and even seizures.
The pet may appear to feel better in this initial stage and give the appearance of having recovered but in a day or two it may get much worse as the kidneys fail. It is in this secondary stage that the damage really starts. Ethylene glycol is rapidly absorbed into the system. When the liver starts metabolising the ethylene glycol it creates a more toxic substance and within 12- 36 hours of ingestion the kidneys may stop functioning and even cause a coma.
Signs of kidney failure include depression and vomiting. Affected animals may drink lots of water and initially urinate in large amounts before urination dwindles to a very small volume.
Taking a poisoned animal to the vet as fast as possible is critical. After the first nine to 12 hours following ingestion of anti-freeze, the liver will begin metabolising the anti-freeze into substances that cause kidney failure and eventually death. Because the early signs of poisoning often those of other illnesses, neither you nor your veterinarian may suspect antifreeze poisoning until it is too late.
Fortunately, your veterinarian can perform in-house laboratory tests – for renal failure and urinalysis – to help correctly diagnose the cause of poisoning.
In unfortunate animals that die six-sided or Maltese-cross shaped crystals of calcium oxalate within kidney tubules that allow pathologists to make the diagnosis.
If you have more than one pet, take care if one vomits and another cleans up the poisoned pet’s vomit. This can result in both animals becoming poisoned.
The good news is that that cats and dogs can be treated for anti-freeze poisoning if the cause is identified before extensive kidney damage takes place. Knowing how much antifreeze has been consumed, although difficult, can assist treatment. Treatment is based on decreasing the absorption of ethylene glycol from the stomach and intestine by assisting with vomiting and increasing its excretion through the kidneys through administration of intravenous fluids. Preventing metabolism of ethylene glycol to glycolic acid and calcium oxalate and correcting acidosis of the blood is also very important.
After accidental research on the effect of alcohol on people that consumed antifreeze this has now been successfully used in veterinary medicine. Pets are administered controlled doses of ordinary drinking alcohol diluted in IV fluids. At the same time sodium bicarbonate is given to reduce the acidity (metabolic acidosis) of the blood. Constant testing the acidity of the urine determines the quantities given.
The faster the treatment the better the chances of recovery. Antifreeze is a nasty poison and one to be mindful of as winter approaches.
Chocolate Poisoning
Death by chocolate
Like everyone else at Easter time my thoughts turn to lessons contained in the Bible ….. Well to be fair, the thoughts go mainly to memories of chocolates devoured over the years as a child.
To my amazement I have discovered there is not one single recorded medical case of people dying from chocolate. I must have come close a couple of times. There are unfortunately regular deaths of Dogs from Chocolate Toxicity. Chocolate contains Theobromine, a Methylxanthine compound which in large amounts can cause increased heart rates, cardiac arrhythmias, arrest and death.
White chocolate contains the least Theobromine, sweet chocolate a moderate amount and dark or cooking chocolate contains the most. The LD50 or dose at which 50% of dogs could die is around 20g of dark chocolate per kg. Dogs are more sensitive to the effects of this compound; their livers metabolize it slowly, converting it to other toxins and take a long time to clear from the body.
Obviously with the poisoning effect being weight related it’s the Toy Breed dogs that are most at risk. A 3 kg Chihuahua would only require one whole small 60g bar of dark chocolate to be at serious risk of collapse. A 40kg Labrador could probably still give 2 king size blocks a nudge, to get into difficulties, seemingly lacking the feedback switch which shuts off their ravenous appetite.
Humans are thought to be around 4 times less sensitive to its effects. This combined with much greater body weights, a reasonable appetite feedback loop and an added tolerance in coffee drinkers explains the lack of human deaths. I’d have to eat about 10kg of baking chocolate, even the thought of which is causing me stomach pains.
Any dog which has eaten a large amount of chocolate relative to its body weight needs immediate veterinary care. With so much chocolate hidden around our homes this weekend lets be extra careful to not let the pooches get their hungry little paws on it. Easter Eggs are truly a hidden danger to our canine friends.
Poisonous Sweets
No Smint No Kiss I’m often asked by concerned pet owners about what common substances may be toxic to their furry extended family. The topics we discuss include some of the common things like chocolate, onions & lilies and then expand into medicines like Dettol and Paracetamol. All the above substances being potentially fatal.
The latter is especially deadly in cats. Lately more unusual things such as tap water and preservatives are getting a lot of discussion as to their possible effect on our pet’s health conditions such as skin allergies. One of the latest findings in a study of dogs in America was particularly interesting to me and I thought I should pass it on.
A pattern was noticed of dogs presenting at vet clinics with marked vomiting and lethargy after the ingestion of Xylitol. Xylitol is a sugar alcohol used as a sweetener in various products including breath mints and sugar substitutes. In addition to vomiting and lethargy, many of the dogs had widespread hemorrhages in the mouth or intestinal tract.
Blood tests performed on all dogs showed a similar picture of hypoglycemia, serious liver enzyme elevation, loss of liver function and damage to red blood cells and clotting cells. Despite concentrated treatment efforts, in some cases including transfusions, more than ½ of these poor guys didn’t pull through. Autopsies showed sévere liver damage with lobular collapse.
Hepatic failure after ingestion had not previously been reported. Because an increasing number of consumer products contain Xylitol, pet owners should be aware that ingestion of Xylitol can have serious, life-threatening effects.
Please think twice before using human medicines, or before sharing processed human foods with our pets. In many cases their bodies utilize and eliminate these compounds very differently to their human minders, unfortunately sometimes with severe consequences.
Slug Bait
Dear Alex,
I have a retriever called Rusty who is a real pig. Sometimes when we’re out walking he will even try to eat slug bait out of gardens. I thought dogs were not supposed to like slug bait? Is this bad for him? I have been told by some people this could kill him. Is that true?
Sarah, Freemans Bay.
Dear Sarah,
The short answer is NO. It’s not safe to have Slug Bait anywhere near your dog. The fact is that Rusty being Retriever is therefore born to eat, like Labradors, Dalmations, Schnauzers and other gastronomically challenged breeds.
I have several clients with dogs like this that “carry the wolf gene” as far as food goes and it does get them into trouble from time to time. These poisons can be labeled as “dog-safe” and do have repellent to discourage some things from eating them, unfortunately this is far from foolproof. Slug bait poisons are a real killer. If your dog eats any slug bait you must seek veterinary attention immediately.
If you’re at home you can try and induce vomiting yourself by pouring a mixture of very salty water from a plastic bottle down the dog’s throat, a two litre soft drink container is ideal. In saying this vomiting should not be induced for ant bait or other caustic poisons.
Veterinary treatment is essential in all of these circumstances. Signs your dog may have ingested slug bait poison could include tremors, in-coordination, excessive salivation and hyper ventilation.
Veterinary treatment may include administering charcoal, fluids, sedatives and oxygen. The chance of a full recovery all depends on how quickly you respond in this kind of situation
Toxic Waterways
This fantastic weather we’ve all been enjoying has also got our pets outside being super active and having their own set of great adventures. Not surprisingly the incidence of mishaps rises correspondingly. One summer culprit that can be found lurking in some of our fresh and brackish water areas is a lethal threat to our pets, to livestock and to humans.
Whilst we would like to think of our waterways as pristine, clear and un-spoilt, chemical and waste runoff can make this far from the truth. Blue-green algae hang at the edges and contain cyanobacteria, primitive photosynthetic organisms, some of which can produce cyanotoxins. These toxins can attack the body’s neurological, liver and skin organ systems.
Each type of bacteria produces distinct toxins and thereby attacking different systems. In New Zealand this will most commonly be a neurological toxin. These natural chemicals bind to ACH receptors in an animal and can kill within Minuits, leaving very little trace. Specialised laboratory tests on stomach contents can be used to confirm this cause of sudden death if the post mortem samples are sent with a specific request. Some of the hot spots for cyanobacterial toxicosis include the Waikato and Bay of Plenty river and lake systems.
With many people unaware of the presence of this toxin, it is highly likely that a significant number of undiagnosed sudden deaths in these areas could have been caused by this organism. Local councils play an important role in reporting the presence of toxin producing blue-green algae in their individual areas, many having large risk signs displayed.
Unfortunate dogs are usually affected by drinking algae laden water in eddies and pools at the rivers edge. Contrary to popular belief the water does not need to be sitting still. Affected dogs will initially present confused and seeking attention or reassurance.
Respiration and heart rates rise and the white third eyelids can slide half way across in-front of the eyes. Signs progress to stumbling, in-coordination and then convulsions. With severe cases breathing will eventually become very shallow, tongues and gums blue from asphyxia and the heart will arrest.
This tragedy can all unfold in as little as 30 Minuits. Please be aware of this potential cause of poisoning. Don’t allow your canine friends to drink from fringing water with algae obviously present, direct them instead to some fast flowing, clear freshwater.
If you suspect possible poisoning or observe any of the signs I have discussed please rush to the closest vet to get potentially life saving assistance. Kind regards, Dr Alex Melrose.