Quick: Think of the traditional stereotype of a typical marijuana user. Popular culture has long depicted people who smoke cannabis as rebellious teenagers (or shiftless adults living in mom’s basement).

That public image, however, is quickly shifting. As marijuana becomes increasingly legalized and socially accepted, soccer moms and CEOs are perusing different strains at sleek, Apple Store-like dispensaries, while politicians’ talk of former marijuana use elicits nothing but shrugs. (We’ve come a long way from “I didn’t inhale.”)

Your employees may also be partaking, for a variety of health-related reasons.

To date, marijuana has been legalized for medicinal use in 34 states and the District of Columbia—and 10 states (plus the District of Columbia) have even legalized recreational use of the drug. But even with the drug’s increased popularity and use, comprehensive studies on the benefits and risks of marijuana have been hampered by the federal government’s classification of marijuana as a Schedule 1 drug.

That means the pros and cons of marijuana use haven’t yet been fully identified, and there remain numerous unknowns.

But with more and more states legalizing marijuana for medicinal and recreational use, here’s what we know—and what employers should know—about the various reasons employees may use cannabis, and what its effects might be.

Anxiety, Depression, and Psychiatric Disorders

Marijuana is well-known to have a relaxing effect on users, so it makes sense that the drug could be beneficial for those suffering from depression, anxiety, and even post-traumatic stress disorder. But researchers are finding that it’s small amounts of THC, one of marijuana’s main compounds, that can offer benefits. Taking in too much THC may actually worsen anxiety.

Marijuana use might also do more harm than good for individuals suffering from psychosis or bipolar disorder, and there’s evidence that suggests marijuana may exacerbate schizophrenia (or trigger it in individuals who carry certain genes).

Chronic Pain

Pain relief is one of the most common reasons individuals use medical marijuana, and there’s evidence the cannabis or cannabinoids in the plant can effectively manage chronic pain. Other individuals have reported the drug to be helpful with calming the painful muscle spasms that frequently accompany multiple sclerosis and relieving diaphragm spasms that aren’t responsive to other medications. 

It’s also worth noting that in states where medicinal marijuana has been legalized, the number of prescriptions written for opioid use has plummeted. Remarkably, states with medical cannabis laws had “a 24.8% lower mean annual opioid overdose mortality rate compared with states without medical cannabis laws.” Cannabis is not without its dangers, but death from cannabis use is extremely rare, and is usually attributable primarily to risky behaviors (e.g. driving under the influence) instead of the drug itself.

Nausea

Another common reason for marijuana use is to ease the nausea and vomiting that may accompany chemotherapy. But others have found that chronic usage of the drug has actually resulted in a cyclic vomiting illness—recurrent episodes of incapacitating nausea and vomiting that are often separated by relatively symptom-free intervals. In one study, the illness resolved itself when marijuana use was stopped, but the cyclical vomiting returned when the individuals resumed their marijuana use.

Sleep

Cannabis or cannabis-derived products are also used by those who find that the drug helps them relax and fall asleep. But while it may help people fall asleep, there may be a price to pay, by way of lower-quality REM sleep phases. This means that while marijuana users might see a modest increase in the amount of sleep they get, they may not be enjoying the deep sleep that helps them feel rested. However, studies are sparse, so it’s very possible that new information will come out.

Lung Health

The good news is that evidence suggests those who smoke only marijuana don’t suffer from impaired lung function—even if they’ve smoked daily for 20 years. Perhaps even better news is that one study found smoking marijuana resulted in increased lung capacity—the opposite of what tobacco smokers experienced. While the exact reason for this increase is unknown, researchers hypothesize that it’s due to the deep breaths users take while smoking—not any therapeutic chemical in marijuana. But perhaps the best news for marijuana users is that they aren’t at an increased risk for cancers associated with smoking.

Heart Disease

Most recent studies conclude that the risk of marijuana-related cardiovascular events is low for healthy individuals, but some researchers suggest that individuals with an elevated risk for heart-related complications should avoid using cannabis. This warning is thanks to the temporary effects cannabis can have on the cardiovascular system, like the increase in heart rate for up to three hours after smoking that might increase the chance of a heart attack.

Pregnancy

While there are clearly some potential benefits to using marijuana, there’s one group for whom the drug offers no added benefit: unborn babies. Expectant mothers might think using marijuana is a safe way to treat their morning sickness, but usage may cause an increased risk of pregnancy complications. Prenatal exposure to the drug may be responsible for developmental and health problems in children, like decreased birth weight, anemia, and impaired memory and attention.

Marijuana and the Workplace

The legality of marijuana is still a point of contention between the state and federal governments, which means there are a variety of ways employers can treat marijuana use in the workplace. Some states defend the employer’s right to enforce a marijuana-free environment, while others make it more challenging to regulate an employee’s use of the drug.

As marijuana use increases in popularity—and legality—it’s critical for employers to ensure their drug-testing and usage policy stays current with local legislation, paying particular attention to how medicinal marijuana in the workplace is addressed. If you do have a drug-testing policy, be aware that THC can remain detectable days or even weeks after cannabis use.

And what of impairment? That depends. Much like alcohol, everybody has a different tolerance. Two employees could consume the same amount of the same strain of cannabis at the exact same time, and one would be impaired for much longer than the other. Impairment time depends on a multitude of factors, so if marijuana use is legal in your state and you witness an employee smoking a joint on Saturday night, they may not be impaired at all on Monday morning. Or, they might. Being alert for signs of impairment in your employees is a sensible approach. To be on the safe side, however, consult your legal counsel to ensure your policies comply with state regulations while protecting the health and wellness of your employees.

While marijuana does hold promise in helping employees resolve chronic pain, reduce anxiety, and just feel better overall, usage isn’t without its risks. Using your corporate wellness program to educate staff and employees can help ensure that your workplace remains a safe, productive one.