Each year more than ten thousand dogs and cats are
accidentally poisoned with automotive antifreeze/coolant. One step
owners can take to prevent a potential tragedy is to use the less-toxic
propylene-glycol-based antifreeze in the car. Propylene glycol -
although not entirely nontoxic - is considerably less toxic than
ethylene glycol. Although dogs and cats account for most cases,
ethylene glycol is toxic to all animals - including people. It is one
of the top ten causes of poisoning in dogs and cats in the United
States. The toxic ingredient is its major component and makes up 95% of
the product. It only takes a small sip of antifreeze to poison your
pet; a few ounces are lethal. Cats are approximately four times as
sensitive to the poison as dogs. For a medium sized dog, ingestion of
about 2 ounces (3-4 tablespoons) is toxic. For a cat little as
1/4 of an ounce (1-2 teaspoons) can be lethal. The problem is
compounded by the fact that this stuff has a sweet taste and when
animals find it, they enjoy the taste.
Antifreeze poisoning commonly
occurs in spring and fall when car owners replace the old antifreeze
with fresh antifreeze in their car radiators. However, poisoning can
happen anytime, particularly when a car boils over or a hose leaks.
This poisoning happens often to animals who are allowed to roam freely
in their neighborhoods, but another high risk group is dogs who are
confined in garages and who may not always be provided with adequate
fresh drinking water. Additionally these dogs may gain access to
improperly or inadequately stored antifreeze or lick spilled or leaked
antifreeze off the garage floor. If it is necessary to confine your
pet(s) to your garage, make sure antifreeze containers are well secured
and your animal has plenty of fresh water. Spills can be cleaned up
with kitty litter as an absorbent, being sure that you remove and
dispose of the litter quickly and completely, then a thorough flushing
of the affected area. Antifreeze is biodegradable but it may take
several months.
Ethylene glycol is also found in
brake fluid, liquid rust inhibitors, hydraulic fluids and solar
collectors. Another source is ethelyne glycol 2% in the liquid placed
inside of decorative “snow scene” glass globes which one inverts to see
the flocculent snow fall. Be sure to protect not only your pets but
your children from breaking and possibly ingesting material from these
decorative items.
Ethylene glycol has an immediate
and a long-term affect on the body. It is rapidly absorbed and
metabolized once it has been consumed. Peak blood levels occur within
three hours of ingestion. Within thirty minutes after drinking it, your
pet will become ataxic, or drunken, in appearance. This phase continues
for up to six hours. The animal appears to recover but by then the
liver will have begun metabolizing the ethylene glycol into to
glyoxcylic acid, formic acid, and oxalate which destroy renal tubular
cells in the kidneys causing kidney failure with the resulting uremia.
These compounds also seriously damage the central nervous system. There
is no treatment that will reverse this damage.
Dogs and cats can only be cured
when the poisoning is detected before extensive kidney damage has
occurred. Diagnosis is not difficult when an owner presents a pet that
is staggering and drunken in appearance and has seen the animal drink
the antifreeze/poison. It is much more difficult when the ethylene
glycol first reaches the liver because early in this stage the pet will
appear healthy while later in this stage symptoms are multi-systemic
and nonspecific. These signs can be confused with other diseases such
as pancreatitis, acute gastroenteritis, diabetes or other forms of
kidney disease. By the time ethylene glycol metabolites have attacked
the kidneys it is too late for a cure. By this time the animal is very
sick from uremia and acidic blood (acidosis). In unfortunate animals
that die, it is the six-sided or Maltese-cross shaped crystals of
calcium oxalate within kidney tubules that allow pathologists to make
the diagnosis in a post-mortem exam. Sometimes the urine of affected
pets will glow when exposed to a woods or ultraviolet lamp.
The amount of ethylene glycol the
animal consumed is very important in determining the success of
treatment. Animals do not respond favorably to any treatment when they
have ingested too much. Treatment is based on decreasing the absorption
of ethylene glycol from the stomach and intestine and increasing its
excretion through the kidneys. Preventing metabolism of ethylene glycol
to glycolic acid and calcium oxalate and correcting acidosis of the
blood is also very important. The first step is to administer
apomorphine or peroxide solution to get the pet to vomit up any poison
remaining in the stomach. Next the animal is given water between
medications in order wash out the stomach thoroughly (gastric lavage).
Finally activated charcoal is administered to bind with any poison that
is left. Large amounts of intravenous fluids are given simultaneously
to increase urine production and excrete as much ethylene glycol as
possible. Treatment was discovered accidentally when a group of
teenagers consumed antifreeze accidentally during a party. It was found
that the teenagers who were the drunkest suffered the least side
effects from the poison. That information is utilized today in treating
pets giving them grain alcohol -To be effective, this must begin within
6 hours after ingestion.
If you suspect your pet had
ingested antifreeze DO NOT hesitate to get them to your veterinarian
immediately. We have shared what is involved in trying to treat this
poisoning to try to impress upon you how serious this condition is. The
only sure treatment is to prevent antifreeze poisoning before it
happens. Be sure that your pet is protected from contact with
antifreeze and coolants - given the chance they will lick it due to the
sweet taste. It's up to you to keep them safe from it.