The time it takes for an edible to hit and the variances in your digestive system on any given day can result in an overdose.

Among the myriad ways of consuming cannabis, edibles are the most unpredictable. Resulting in powerful highs that take their sweet time to get there, edibles produce an equal amount of love and fear from cannabis veterans and newbies alike. Here’s why these products are so different than smoking or vaping cannabis.

For starters, edibles are eaten, which makes almost all the difference. Like medication and food, edibles are absorbed through the stomach lining and your intestines. After the food is broken up, the THC in the edible is absorbed and slowly makes its way to your bloodstream. In contrast, when cannabis is smoked, the effect is almost instantaneous, with the smoke traveling to your lungs and then quickly seeping into your bloodstream. Smoked highs are fast in every sense of the word, entering and leaving your system within just a couple of hours.

Depending on your meals, it can take your body longer to process edibles; if you had a weed gummy after a big dinner, it’ll take you longer than if you’d eaten the gummy on an empty stomach. You might fall asleep before you feel the high and wake up thinking you’ve traveled to a different planet. Not a nice feeling.

Andrew Stolbach, a toxicologist from Johns Hopkins Hospital in Baltimore, explained to Eating Well that the time it takes for an edible to hit and the variances in your digestive system on a given day can result in an overdose.

“Something that’s important to remember about edibles is that absorption is unpredictable,” he says. “People don’t experience peak effect for a while after eating, [which can be] minutes to hours—but usually hours.”

The symptoms of an edible overdose are the same as a smoking overdose, only stronger and longer lasting. The standard side effects of marijuana like paranoia, anxiety and fast heart rate can present themselves for 6 to 12 hours after overdosing on an edible. These effects can become more pronounced if you get scared and start to panic.

Like all things, it takes practice to master edibles, whether you purchased or prepared them in your kitchen. Before consuming an edible, make sure you’re with a person you trust and that you know the dosage that you’re putting in your body. Take your time with it, eating small amounts at first. Let a couple of hours pass and see how you feel.