Places like Colorado, where medical marijuana has been legalized, have seen a spike in the number if pooches getting high.

REUTERS/Baz Ratner A worker tends to cannabis plants at a plantation near the northern Israeli city of Safed June 11, 2012.

Related Dogs Getting High On Marijuana Is An Increasing Problem in Colorado, Vets Say New York Daily News

File under the strangest of unintended consequences. As states throughout the U.S. have slowly moved toward relaxing their marijuana laws, there has been a disturbing surge in the number of incidents involving pets ingesting marijuana, either accidentally or after it’s fed to them by their owners. (There’s even a surprising number of YouTube video results for the search term “dogs getting high.”) Now several veterinarians have come out to warn against the dangers of dogs ingesting cannabis after seeing a spike in sick animals in Colorado.

(MORE: Why Medical Marijuana Laws Reduce Traffic Deaths)

Speaking with CBS 4 in Denver, veterinarian Dr. Debbie Van Pelt said that she has seen “huge spikes in the frequency of marijuana ingestion [among pets] in places where it’s become legal.” Seventeen states across the U.S. have approved the regulated use of medical marijuana, although few states have embraced the trend as much Colorado; by one count Denver has more marijuana dispensaries than it does Starbucks.

In many instances the dogs appear to have eaten their owner’s stash. The affects are far from pleasant for the animals, who start to stagger and vomit and can even lapse into a coma. According to Dr. Pelt: “They basically [lose] a lot of their fine motor control, they have a wide-based stance and they are not sure on their feet.”

(MORE: A New Marijuana Plant Without the High? It Could Be Good Medicine)

While in most cases the effects are short-lived, vets have reported some fatalities as a result of ingesting marijuana. Dr. Stacy Meola, a vet at Colorado’s Wheat Ridge Clinic, told Denver’s CBS 4 that she saw two dogs die after ingesting baked goods containing medical marijuana.

Meola has organized a five-year study looking at the number of dogs that fall ill as a result of the drug. She found that the number of cases of dogs getting high had quadrupled since Colorado legalized medical marijuana in 2000.

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