The new study found that though edibles represented less than one-third of 1 percent of the state’s total cannabis sales by weight of THC between 2014 and 2016, they accounted for 238 of the 2,432 cannabis-triggered visits to the UCHealth University of Colorado Hospital Emergency Department, or about 10 percent. The authors calculated that there was 309 times more THC sold in flower or smoked form compared with edible products during the three-year period examined.

Symptoms also tended to vary depending on whether the pot was consumed as an edible or smoked. Nearly half of the emergency room patients who had consumed edibles complained of intoxication or altered mental status, often accompanied by anxiety, compared with less than a third of those who had smoked the pot.

About a quarter of both the smokers and those who consumed edibles experienced psychiatric problems, but those who used edibles were more likely to exhibit acute psychiatric symptoms, while the smokers were more likely to complain of an exacerbation of a chronic condition like depression.

In addition, 8 percent of edible users had cardiovascular symptoms, including rapid or irregular heart rate, compared with only 3 percent of pot smokers. Serious cardiovascular events, including heart attacks, occurred in both groups. Other studies have also reported on the emerging concern of cardiovascular problems being associated with pot use, Dr. Volkow said.

Concerns about edibles are not new, and many states that have legalized recreational or medical cannabis, including Colorado, California, Rhode Island, Nevada and Oregon, require packaged edibles to carry a warning that the intoxicating effects may not be felt immediately, said Camille Gourdet, a researcher who studies state cannabis policies at RTI International, a nonprofit research organization.

Many states also require edibles to be clearly marked with a symbol warning consumers that the products contain cannabis and are not regular food items, Ms. Gourdet said. Several states also require edibles to have even distribution of THC content throughout the product so it is not all concentrated in a single bite of a cookie or brownie.

Dr. Monte, who sits on the Colorado Retail Marijuana Public Health Advisory Committee, said he does not think edibles should be available in the retail recreational market. He said the important message for consumers is that there are more adverse drug events associated with edibles than with inhaled products, and that edibles are more likely to trigger psychiatric illness. First-time users — a group that, in Colorado, often includes tourists, are at particular risk, he said.