KANSAS CITY, Mo. — Susan Karr says the thing to try when she was growing up was cigarettes.

“And of course I did as a teenager,” the 79-year-old told FOX4.

But the new frontier for some seniors is recreational marijuana, freshly legalized in Missouri, and health professionals are seeing an uptick in ER visits among people over age 65.

The main factors include increased risks of slips and falls and misunderstandings over how to dose their edibles, University Hospital Addiction Medicine Specialist Dr. Doug Burgess said.

One national study said cannabis-related emergency room visits for seniors are up about 1,800% from 2005.

That increase might also be a reflection of more nuance in the health care system. Instead of an injury being considered just as a broken pelvis, for example, it might be coded as a fall while under the influence.

But another factor is that many seniors aren’t aware of their limits. Karr said she has no reference as the drugs aren’t really on her radar.

“I’ve not tried any of it, and I don’t really know that much about it,” Karr said with a laugh.

Her son said that didn’t surprise him.

“When you get to that demographic, the older demographic, they’re typically on a whole bunch of medications, right? So you’d have to at least consult with your doctor,” he said.

Karr said if she were to look into edibles or other marijuana options, she wouldn’t know how much to take.

“I would like to look it up. I would have to find out as much about it as I could if I was trying to go that route,” Karr said.

“So for example, a brownie might have 100 milligrams of THC, which would be anywhere from 10 to 20 doses,” Burgess said.

Burgess said the effect also may last longer in seniors than in younger people.

“So it can certainly increase confusion, can impair cognition, increase risk of falls,” Burgess said.

Benjamin Franklin Brown said he’s used marijuana, but it was way, way back. Even with experience he’s unsure of edibles now at 72.

“You have a brownie that’s dosed for 10 times. And then, if you don’t really know and you’re older you think, ‘Oh, this brownie’s pretty good. I’m going to eat the whole thing.’ And then you start freaking out. Can you imagine something like that happening?” FOX4’s Jacob Kittilstad asked.

“Yeah, that happened to me once in Florida when I was on it. I went down to Florida. I was about 26. They gave me some stuff and my hotel was right there, and I kept walking up and down the beach. My wife come out there and said, ‘What the hell you doing?!'” Brown said.

His advice: Take it slow and don’t do it alone — if you want to stay out of the ER.

“You know why they end up there? ‘Cause they’re afraid of dying. And when it makes your heart beat fast, they get scared and run straight to the ER,” Brown said.

Another things doctors are telling their senior patients: Pot today is stronger, not like weed from the ’60s, which may be the last time those patients have used.