Waking up through anesthesia in the middle of surgery is a worst-nightmare scenario.

But it happens — as terrifying as that sounds. And, apparently, for regular marijuana users, it’s a scenario that’s not exactly outlandish.

According to a study published in the Journal of the American Osteopathic Association regular cannabis users do not react the same way to anesthesia as non-users. Sadly, this miracle flower weakens the effects of some common anesthetic drugs, making the job of an anesthesiologist more difficult.

“Researchers found that compared with people who did not regularly use cannabis, people who regularly used cannabis required an amount of sedation for endoscopic procedures that was significantly higher,” the study’s results read.

That is not exactly reassuring news when you consider that using anesthesia is such a delicate and potentially deadly ordeal.

The researchers found that, for very common drugs like Propofol (which helps people stay asleep during surgery), cannabis users required as much as three times the normal dosage. Which can raise other health complications for a person, like low-blood pressure and breathing problems.

Our doctors need more information; they need research on how cannabis affects the anesthetic drugs that they use. But until cannabis is decriminalized or outright legalized at a federal level, that’s probably not going to happen. Getting funding for, and executing a legit medical cannabis study is not easy in a country where it’s classified as one of the most dangerous drugs known to man.

Until then, the best policy is honesty. If you use cannabis regularly (and particularly if you used the same day of your surgery), you should definitely disclose that to your doctor before they start pumping you full of chemicals and cutting you open.

Lest you risk waking up under the knife… or worse.

“Determining cannabis use before procedural sedation can be an important tool for planning patient care and assessing both medication needs and possible risks related to increased dosage requirements during endoscopic procedures.” The Study concludes.

So speak up if you toke up. It’s for your own good. Your doctor won’t narc on you (even if you live in a state where weed’s illegal), they’ll be happy you told them.