Poisoned pets need life saving treatment quickly
Poisoning is a common emergency in pets: like young children, animals have no awareness of the danger of ingesting certain substances. It's up to owners to protect their pets by keeping all poisons out of reach, but even with the best efforts to avoid it, poisoning of pets happens regularly. There are three common causes.
First and most commonly, pets somehow manage to get access to poisons without their owner realising it (e.g. stealing chocolate or pharmaceutical products or finding something toxic to eat while out on a walk).
Second, owners are sometimes not aware of the danger of a substance, so their pets are exposed to something without their owners realising there's a toxic risk (e.g. cats coming into contact with Lilies)
Third, and rarest, poisons are sometimes used in baits to maliciously harm pets.
Dogs are more commonly poisoned than cats: they are scavengers by nature, eating first and asking questions later, so they are more likely to eat something that's bad for them. Cats, in contrast, ask questions first and eat later: they'll sniff delicately at a substance before deciding to eat it. This caution protects them against some poisons, but to counter this, a cat's metabolism is more sensitive than a dog's, causing them to be uniquely sensitive to some substances (e.g. Lily pollen and paracetamol). Furthermore, cats tend to be more private individuals than dogs, so if they do ingest poison, it's less likely to be noticed by their owner.
There are two situations when pets need to be taken to the vet for poisoning.;
First, when an owner has witnessed the animal eating the poison, before there are any signs of the pet being badly affected. This is the ideal scenario: in many cases, the poison can be removed before it has had time to be absorbed into the animal's system, and pre-emptive treatment can sometimes be given to counter the expected effects of the poison. It's really important that such cases are taken to the vet as soon as possible, ideally with as much information as possible about the substance that has been ingested (e.g. label of drug, sample of capsules, photo of plant.)
An example would be a dog that has been known to eat a stash of rat bait: the vet will be able to empty the dog's stomach by causing vomiting, prevent further absorption from the digestive tract by giving activated charcoal, and give Vitamin K supplementation to counter the effects of the poison.
There's a surprisingly narrow window between ingestion of a poison and absorption into the system: ideally, vomiting should be induced within two hours of the poison being eaten, and the sooner the better. The longer the poison is in the stomach, the more will be absorbed.
There are some specific situations where vomiting should not be induced: if an animal has eaten a caustic or corrosive substance, vomiting would make things worse by causing further irritation and damage to the oesophagus and oral cavity.
In the past, owners have sometimes tried to cause vomiting in their own pets (by giving salt or other substances) but this can be dangerous, and should not be attempted. Vets have injectable products that can predictably and safely cause vomiting in a controlled way. Occasionally (e.g. if an animal is unconscious), the stomach may be pumped out instead (so-called "gastric lavage"): this can be highly effective but it does require a general anaesthetic, and it doesn't offer much advantage over vomiting in cases where this can be induced.
Once the stomach has been emptied of poison, the next step is to try to prevent absorption of the poison from the intestines: this can be done by giving activated charcoal, which "mops up" many poisons, stopping them from crossing the intestinal wall into the blood stream. Sometimes cathartics are also given: these speed up the rate of passage of the intestinal contents (causing diarrhoea), so that the poison is hurried quickly out of the digestive tract.
With luck, the early removal of poison from the pet's system can be enough to prevent the onset of the signs of poisoning, but in many cases, these efforts are only partially successful. Further treatment by the vet is needed to help the animal deal with the effects of the poison.
Such cases then need to follow the same course to the second situation when poisoned pets are taken to the vet, when the ingestion of the poison was not noticed initially, and the pet has started to show signs of poisoning. In both situations, the animal is visibly unwell. Life saving action by the vet is critically important.
This is more complicated than you might expect: there are very few poisons with highly effective antidotes, and it's nearly always a case of using medication to support the animal's health until the effects of the poison had worn off naturally. Sedatives and relaxants may be needed to stop muscle tremors and seizures, intravenous fluids will be given to keep the circulation working as effectively as possible, and good nursing care is essential to keep the animal comfortable until the poison has been effectively metabolised by the body. Treatment can last several days, with around the clock care being needed.
The best answer? Be very careful to ensure that your pet is never poisoned.