DENVER - In some cases, the victims don't realize they've consumed pot.
University of Colorado Senior Sarah Meyer is getting ready for final exams. A change from last Friday, when she thought she was going to die.
"I was light headed. Dizzy," said Meyer.
The reaction after police say two of her classmates served marijuana laced brownies at a lecture, an apparent prank.
"I really felt something was wrong. I didn't feel like myself. I didn't understand why I was feeling this way. So I thought it was a blood clot," said Meyer.
7NEWS checked with Rocky Mountain Poison and Drug Center..
Over the past three years - the number of marijuana ingestion cases has been growing steadily.
"Are those numbers an accurate reflection of the the problem?" asked 7NEWS reporter Marc Stewart.
"I think they're probably under reported by half," said medical director Alvin Bronstein.
While the reasons for that vary, with more marijuana expected on the marketplace - the numbers could grow even further.
"I think as time goes by we'll see more exposures to marijuana. Because it's more available. People are exposed to what's available," said Dr. Bronstein.
Cases like Sarah Meyer's where someone is unknowingly poisoned are described as rare - but she will tell you just as serious.
"It took a lot of time out. And like very stressful," said Meyer.