Activated charcoal is a form of carbon that filters out toxins. It provides a surface that other substances can bind to, which how it helps in the case of toxins. Once bound to the charcoal, the toxin can’t be absorbed into the bloodstream and will pass out of the body in the feces.
Not all toxins bind well to activated charcoal, however. For example, acetaminophen (Tylenol) and digoxin (a heart-failure drug) bind well, but alcohol and ethylene glycol, such as is found in antifreeze, do not. It is often used when dogs ingest rat poison, which is common.
The first step if your dog ingests a potentially toxic substance is to call an animal poison-control center. Yes, there is a charge, but the staff are extremely well educated in poisons. Even veterinarians sometimes call these centers, so don’t be surprised if your own veterinarian recommends you contact a center.
The veterinarians and veterinary technicians staffing the poison-control center can tell you if giving activated charcoal makes sense. In some cases, it may be contraindicated, for example, if your dog is at risk of aspiration pneumonia. Call:
Administering Activated Charcoal
Giving activated charcoal is a challenge, which is a strong reason you may want to hustle to your veterinary clinic for help. It should ideally be given within an hour of ingesting the toxin. If your dog is already showing signs of poisoning such as tremors, it is too late as the toxin has already been absorbed.
The recommended dose of activated charcoal for your dog is about 1 gram per kilogram of body weight. It is messy to administer. While it can be given in powder or capsules, human studies show that it is most effective if given as a suspension (crushed and mixed with water). If you are lucky, your dog will eat it mixed with some very wet dog food (add water and make a slurry). In some cases, the veterinary clinic may decide to administer it to your dog via a tube directly to your dog’s stomach.
Some versions of activated charcoal come with a cathartic (laxative) such as sorbitol (a sugar alcohol). This type of activated charcoal should only be used for one dose, and your dog’s electrolytes and hydration status will need to be monitored.