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As medical marijuana moves into the mainstream in many states, it puts employers in a tricky situation: How do you handle it when an employee takes small amounts—known as microdoses—of THC throughout the workday to manage a medical condition, whether it’s headaches, anxiety, or pain?

Is it the same as taking a Tylenol? Is it safer than an opiate? And do employers need to know?

“This is an unbelievably complicated issue,” said Mary Kay O’Neill, a senior clinical consultant for HR consulting firm Mercer.

In fact, complying with marijuana laws is one of the biggest challenges facing employers in 2020, according to a survey of 700 HR professionals by XpertHR, an online HR resource site. Nearly a quarter said they are extremely challenged by federal, state, and local medical and recreational marijuana laws and managing employee drug use, compared with 5.7% in 2017. Rapidly changing laws, they said, have created complications for employers who want to implement drug-free workplace policies.

It’s almost impossible for national companies to navigate this territory when they’ve got workers scattered across multiple states—including those where marijuana is still illegal. Employers with federal contracts must also be careful to abide by federal Drug Enforcement Administration rules. “It’s just a hodgepodge out there,” said O’Neill.

Though medical marijuana is legal in 33 states, the drug is still illegal at the federal level and is categorized as a schedule I drug by the DEA. And because of that, there’s very little research showing the efficacy of cannabis for a variety of medical conditions, whether it’s multiple sclerosis, neuropathy, anxiety, or depression, said Reema Hammoud, director of clinical pharmacy at health insurer Sedgwick.

That hasn’t stopped people from taking large—and small—doses of THC. Oklahoma, for instance, saw the number of people with medical marijuana cards surge to 200,000 in a matter of three months last year—making up at least 5% of the state’s 4 million citizens. Meanwhile, U.S. sales of small-dose THC products—usually oils and edibles that deliver 2.5 milligrams to 5 milligrams of THC at a time—jumped 45% last year, and 23 new small-dose products hit the market, according to BDS Analytics, which tracks marijuana sales. But those sales were still at the micro level, representing 1.3% of the overall $1.13 billion edible market.

“You’d be surprised how many people are microdosing during the workday,” said Bonni Goldstein, a doctor who runs Canna-Centers, an L.A.-area medical marijuana clinic, and a medical adviser to WeedMaps.

The goal of microdosing is not necessarily to get high. Cannabis can be psychoactive—though not always intoxicating—meaning it alters a person’s perception of pain, anxiety, ADHD, insomnia, depression, and more. The effects of 2.5 milligrams or 10 milligrams will vary person to person, depending on the balance of their natural cannabinoid receptors. True patients, Goldstein said, are not looking for an intoxicating effect. “They’re seeking a balanced state.”

But how can an employer know the difference? And should they even ask if a worker is microdosing on the job?

The answer differs case by case. Using THC at work would be more worrisome for a truck driver or bulldozer operator, while a microdosing receptionist may be of less concern.

As marijuana becomes more prevalent, however, employers are changing their stance toward the drug. A number of big companies—such as AutoNation, the largest U.S. car retailer, and Excellence Health, a Las Vegas–based health care company with 6,000 employees—have stopped drug testing and axed their zero-tolerance drug policies.

That’s in part because testing for marijuana isn’t perfect: Cannabis may stay in the blood system for days after a person has used the drug—even if he or she is not high. A weekend joint is considered by many to be the same as a couple of beers.

“A lot of great candidates were failing the test,” AutoNation spokesman Marc Cannon told the Los Angeles Times last year. “Marijuana is just like alcohol.”

But when it comes to using on the job—even in small doses—employers have mixed reactions. A small dose of THC may get one person very high while it may not affect another. And without industry standards from the Food and Drug Administration, the real THC dosing can vary by product and experience.

“I think it’s a situation of, ‘Don’t ask, don’t tell,’” said Chris Golden, CEO of Rye Electric, an L.A. construction company that dropped its zero-tolerance policy for employees in 2018. “I honestly don’t want to know.”

Some experts even suggest that employees don’t necessarily need to divulge their habit of taking small doses of THC during work hours. If a person took medication for high blood pressure or a kidney problem, for instance, that would be considered private health information.

Not surprisingly, most workers find themselves tiptoeing around the issue of THC at work. Kevin, a 30-year-old pharmacist who asked to be identified only by his first name, informed his employer that he takes 2.5 milligrams to 5 milligrams of THC oil each day for neuropathic pain in his leg, stemming from a car accident as a teenager. Kevin said his employer was okay with his medicinal use of the drug, but he seldom tells others about his microdosing. A key reason: There’s still a stigma when it comes to cannabis.

Though Kevin has a prescription for various painkillers and opiates, he prefers a microdose of cannabis instead, because he doesn’t get high. “A little bit of THC at a very low dose makes the pain more manageable, but I’m not impaired,” he said.

Not long after his accident, at 17, doctors offered him methadone for pain, but he declined. As he left the clinic that day, the doctor caught up to him in the hallway. “He said, ‘Hey, I’m going to tell you something you didn’t hear me say. But go buy a bag of weed.’ And I did and thought, ‘Holy crap, it really works.’”

Many employees don’t divulge their microdosing of cannabis for fear of being passed over for promotions or even fired. Yet in the past couple of years, the courts increasingly are siding with employees in marijuana discrimination cases.

New Jersey’s Appellate Court, for instance, recently ruled in favor of an employee and required his employer, a construction company, to cover the cost of medical marijuana used to treat pain resulting from a workplace injury. And, under state civil rights laws, at least 19 states now provide legal protection for employees in cases of discrimination when it comes to marijuana use.

“We’re advising employers on a case-by-case situation,” said Dori Stibolt, a Florida employment attorney at Fox Rothschild. “Tread carefully. What you can decide for one employee may not be fit for another.”

As anxiety mounts—with more people working from home amid the COVID-19 pandemic, and marijuana dispensaries remaining open under state lockdown orders—experts predict that the prevalence of microdosing may only grow.

“As a society we trust people with very dangerous medicines,” said Goldstein. “It’s up to people to be responsible.”

What employers need to know about employees microdosing cannabis at work

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