The length of time that CBD stays in a dog’s system can vary depending on several factors, such as the dog’s age, weight, metabolism, the amount of CBD administered, and the method of administration.

In general, the half-life of CBD for dogs is thought to be between 4-12 hours, which we will explain in greater detail below. The compound itself, however, can remain in their system for up to several days or even a few weeks. The exact duration of CBD in a dog’s system can depend on various factors such as the dosage, frequency of use, and the individual dog’s metabolism.

It’s also important to note that there is limited research on the pharmacokinetics of CBD in dogs. However, some studies suggest that CBD is generally well-tolerated in dogs, even at higher doses.

Half-life elimination curve (source: Chemistry LibreTexts, CC-by-4.0.)

CBD’s half-life

When discussing how a substance is active in the body, you’ll see a lot of talk about ‘half-lives’. Half-life refers to the length of time it takes for the concentration, or amount, of a particular substance in the body to decrease to half.

Drug half-lives matter for manufacturers and four-legged patients, because they help determine dosage. If you’re looking for a treatment that lasts all day, but you only want to administer it once, you’ll need something with an elimination half-life of at least twelve hours.

A short half-life “may require more frequent dosing in order to maintain desired exposures and avoid unnecessarily high peak concentrations.”

An overly long half-life, on the other hand, can have a prolonged “accumulation and subsequent elimination”.

The consensus on the elimination half-life of CBD in humans is between 18 and 32 hours, so anywhere from a day to a day-and-a-half.

This is when CBD is ingested orally. Another method of delivery will likely result in a speedier half-life.

Of course, those numbers relate to humans—so what’s the half-life of CBD oil for dogs?

The body of research is much thinner, meaning that numbers are less conclusive. But, we know that CBD interacts with via the same biological mechanism (the endocannabinoid system) in people and dogs.

We also know that dogs have faster metabolisms than us, hence the concept of dog years. These pieces of information suggest that CBD is processed by dogs in a day or less.

Current studies back up this assumption, with a 2018 study published in Frontiers in Veterinary Science puts the half-life at just over four hours for our four-legged friends.

The anecdotal evidence

The science is only one side of the coin, however. For a full picture, it’s important to see whether conclusions drawn in the lab match up with the reality of how CBD is being used by dogs and owners in everyday life.

It seems that most pet owners advocate for an eight-hour dosage—so, one or two lots of CBD per day. When, and how much, those dosages consist of is going to depend on the purpose of CBD treatment & the specific CBD oil.

Owners looking to maintain a consistent level of CBD in their dog’s system, should veer towards lower, twice-daily doses. Those looking to treat for specific incidents such as panic triggers may want to consider a single, more concentrated daily dose.

The verdict

CBD stays in a dog’s system for four to twelve hours—depending mostly on their size and age

While we’re still waiting for the science to provide an exact number for the half-life of CBD in canines, the data we do have supports what owners already seem to know.

Dogs can process CBD more quickly than humans, thanks to their faster metabolisms. This means that, in general, CBD stays in a dog’s system for four to twelve hours—depending mostly on their size and age.


  • The duration of most substances is measured in half-lives. This is the time taken for a substance to halve in concentration in blood plasma.

  • Most of the research of CBD’s half-life has taken place in humans. For us, CBD seems to leave our body in a little over 24 hours.

  • The faster CBD is introduced into the bloodstream, the shorter the half-life is likely to be. Oral ingestion is typically a slower form of delivery.

  • Dogs have a faster metabolism than humans. Because of this, they’re able to process CBD more quickly—science puts the number at around four to twelve hours.

  • Many owners use an eight-hour dosing schedule. But close observation of your dog’s behavior should always be the most important factor in deciding dosage levels and frequency.