Medically Reviewed by
Jason Crawford

Article Last Updated on January 4, 2023

Did you know that the use of police dogs in law enforcement started in 1899 in Belgium? At the time, Wolfhounds and Belgian Shepherds were the first canine breeds known to be trained to assist police officers. As years went by and this practice proved to be successful, finally, in 1907, two Belgian Shepherds were brought to the U.S. from Belgium and it’s all history from there.

Police dogs are now regular members of staff in law enforcement because of their extraordinary sense of smell. They are trained to sense not only guns and explosives, but also illegal substances. Since marijuana is illegal on a federal level, police dogs are also trained to smell marijuana and marijuana products, but is it the same with marijuana edibles?

Whether you use edibles as medical marijuana or for their recreational effects, you might wonder if edibles smell differently and whether dogs can sniff them or not, which is the main topic in today’s article.

Do Edibles Have a Smell?

What makes weed smelly are the aromatic compounds called terpenes which are found in abundance in the cannabis buds. There are many types of terpenes all of which emit a certain type of smell that composes the distinct smell of cannabis. However, weed edibles are different. They tend to be much less smelly compared to fresh and dry weed because their chemical composition is different. 

Unlike the buds, marijuana edibles either don’t contain terpenes or most of them are lost during the preparation process. Terpenes are incredibly volatile and can easily combust at higher temperatures.

Generally, dispensary-bought edibles tend to be less smelly than homemade ones because companies usually remove the terpenes via a method of extraction which separates the THC from the terpenes. With homemade edibles, on the other hand, some terpenes may remain in the final product.

For example, weed brownies baked with dry weed may have a more pronounced smell than brownies baked with cannabutter/cannaoil. And edible gummies and other chewables do not emit a strong smell, though some may have a faint grassy undertone if you really look for it.  

So, cannabis edibles will definitely have a smell (they’re food after all), but not as much as you would think, plus it really depends on the type of edible. But, the question is – can drug dogs smell edibles?

Can Dogs Detect the Smell of Edibles?

To put it plainly, yes, dogs can detect the smell of edibles. Our canine friends have highly developed scent receptors and are 10,000 to 100,000 times more apt at detecting smells than humans. To be more precise, doggos have a staggering 300 million olfactory receptors, compared to humans who only have a modest 6 million. Big difference. 

To add to that, dogs also have a special sensory organ called Jacobson’s organ which enables them to detect “undetectable” smells. Therefore, it shouldn’t come as a surprise that dogs are frequent companions to police officers.

So, we established that dogs can detect all kinds of smells, including cannabis edibles, but the more important question is – are they trained to do so?

The thing is, police dogs are being trained to be able to sniff some very specific things, such as explosives, firearms, sim cards, illicit drugs such as MDMA, heroin, meth, and cocaine, mobile phones, etc. And when it comes to cannabis, they are trained to recognize fresh and dried cannabis, cannabis seeds, concentrates, and synthetic cannabis. 

Then why aren’t weed edibles on the list? Simply, they don’t see any need for it. Most of the time, law enforcement is more concerned about preventing a smuggling operation of large quantities of weed or more dangerous narcotics, rather than a few pieces of edibles that someone carries in their pocket for personal use. 

Do Border Services Still Employ Drug-Sniffing Dogs?

While drug-detection dogs are commonly used in law-enforcement operations, they’re rarely included at border checkpoint stops. When there is no immigration involved, Border Patrol doesn’t include police dogs unless they have a valid need or a reasonable suspicion to do so, or in other words, unless they suspect a crime has been committed.

Additionally, since the gradual state legalization of cannabis kicked in, it seems like the majority of drug-sniffing dogs are being trained to recognize heavy narcotics, such as MDMA, heroin, and cocaine.

How Are Drug Sniffer Dogs Trained?

Not all dogs can be drug sniffer dogs. The canine breeds that are most commonly selected to be police dogs are:

  • Bloodhounds
  • Beagles
  • German Shepherds
  • Basset Hounds
  • Labrador Retrievers
  • Belgian Malinois

The dogs are carefully selected based on their temperament and potential to stay focused on one task at hand. They are trained from a very young age so that the recognition of different smells can become their second nature. Any drug dog trainer will tell you that training dogs is an intense and meticulous process that lasts for months. It can take a year or two before a dog is added to the special canine unit.

At first, dogs are trained to respond to basic commands using a positive stimulus with rewards like treats and toys. They are taught to sit, bark, dig and walk on command. Then the dog trainer will slowly transition to teaching the dog how to recognize different smells and alert the handler with its body language. One of the final stages of training is exposing the dog to a public setting so that it can learn to handle outside distractions and still be able to detect smells without losing concentration.

Training Your Dog to Smell Edible Marijuana

During the training process, dogs are trained to associate the smell of marijuana with their favorite toys. A white towel is the most commonly used item during the training because a small packet of weed can be hidden in it. First, the trainer familiarizes the pup with the object through play. The dog trainer plays with the pup using the white towel as a toy to reinforce positive stimulus. 

Then, after a few sessions, the dog trainer will hide a small packet of weed inside the towel and continue with the game so that the dog will learn to associate this smell with its favorite toy. After a while, the dog will be able to recognize the smell and search for it in various locations. When they recognize the smell and find the location where it’s hidden and alert their handler, they get a reward.


Can a drug dog smell a vape pen?

Drug dogs are able to smell cannabis products such as vape pens because the vape juice found in these devices contains terpenes and other flavorings and aromas. 

Do checked bags get searched?

Normally, checked bags do not need to get physically searched because they get inspected during the screening process. If the TSA finds a reason to physically search through your bags, they will place a notice of baggage inspection to let you know that your bags have been inspected by an officer.

What happens if the TSA finds drugs in checked baggage?

The TSA does not specifically look for cannabis or other illegal substances, but if any are discovered during the routine security screening, the TSA is obliged to report it to law enforcement.


A dog’s sense of smell is much more developed than a human’s, which is why dogs have been a part of law enforcement ever since 1899. That being said, with the legalization of marijuana, dogs are more often trained to recognize heavier drugs, rather than marijuana. They go through a rigorous training process that lasts for months and learn to differentiate between different smells through positive stimuli.

And while dogs can be trained to sniff out a variety of smells, including marijuana, they can’t really smell the weed in marijuana edibles. This is mainly due to edibles being less smelly than fresh and dry weed because they undergo chemical changes during the preparation process and they lose most of the terpenes.

A passionate advocate for the benefits of cannabis. Fraser Horton, who has a background in botany and a strong love of nature, has spent years researching how cannabis affects the body and mind. He established Leaf Nation in 2020, where he has devoted himself to educating people about the legalisation of marijuana and its safe and responsible use. Fraser is committed to highlighting cannabis’ potential for improving wellness and working to dispel the stigma associated with its use.


The information presented on this page is provided as a public service to aid in education and is derived from sources believed to be reliable. Readers are responsible for making their own assessment of the topics discussed here. In no event shall Leaf Nation be held reliable for any injury, loss or damage that could happen if using or abusing drugs.