Every April 20, California dispensaries see a surge of first-time buyers who walk in curious, walk out with a bag of gummies or a pre-roll, and have absolutely no clue what they’ve signed up for.

That’s not automatically a disaster. But it can become one within the hour.

The Department of Cannabis Control requires licensed retailers to post warnings and hand over product information at the point of sale. What that requirement doesn’t address is the chasm between reading a label and grasping what 500 milligrams of THC in a single gummy bag actually does to someone whose body has never processed cannabinoids before. Those are very different things.

It doesn’t take much to go sideways.

A cannabis physician spoke to the physician told the Sacramento Bee about what new consumers get wrong most often around April 20. The pattern he described isn’t new, but it’s worth going through again given how many people treat that date as an invitation to experiment without any preparation.

Start with your dose. Then cut it in half. For inhalable products, one or two puffs is genuinely enough for a beginner. Edibles are where the real trouble tends to happen: someone eats one, feels nothing after 45 minutes, decides it didn’t work, eats a second, and then both doses arrive at once like freight trains. The California Poison Control System tracked a sustained rise in cannabis-related calls after legalization, and edibles account for a significant chunk of those cases.

“Think of it like starting a new supplement,” the physician said. “You wouldn’t double the dose because you didn’t feel it in 20 minutes.”

Know your product before you buy it.

THC percentage on a flower label doesn’t tell the whole story. A flower testing at 28 percent THC smoked fast hits very differently than the same product consumed slowly over an hour. Concentrates can run 70 to 90 percent THC. A first-timer has no reason to start there. CBD-to-THC ratios also shape the experience considerably: a product with roughly equal parts of each tends to produce something milder and more manageable for someone new to cannabis than a high-THC product with no CBD present. The National Institute on Drug Abuse has documented how blood THC levels correlate with impairment in ways that can catch inexperienced consumers completely off guard.

Your setting matters as much as what you consume. Don’t use cannabis alone the first time if you can avoid it. Have someone nearby who’s either sober or experienced enough to stay calm if the night takes a turn. Don’t drive afterward. And don’t consume at a large outdoor event where leaving or finding somewhere quiet to sit isn’t really an option.

The anxiety spiral is the most common bad outcome first-timers report. It’s not dangerous in a clinical sense, but it feels terrifying in the moment. The response is straightforward: sit down, drink water, don’t take any more cannabis, and remind yourself the feeling will pass. If someone with you is panicking after consuming, those same steps apply. Stay calm. Get them seated somewhere safe. Don’t call 911 unless something physically medical is happening, because an elevated heart rate and a wave of dread, while genuinely unpleasant, don’t constitute an emergency requiring paramedics.

April 20 brings real joy to a lot of people. It can also bring a very bad 4 or 5 hours to someone who didn’t read anything before walking into a dispensary. The information is out there.