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Friday, October 30, 2020  Spokane, Washington  Est. May 19, 1883
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Little research available on risks of combining cannabis, prescriptions

Providers can answer questions about mixing meds

Patients who are prescribed medication who also are regular users of cannabis should check with their health provider about possible risks of combining both products.  (Trish Merryman / Evercannabis Staff)
Patients who are prescribed medication who also are regular users of cannabis should check with their health provider about possible risks of combining both products. (Trish Merryman / Evercannabis Staff)
Many of us have faced a familiar temptation. Following a spirited night of drinking, we can’t sleep. So we look in the medicine cabinet for something to help us nod off. If we’re smart, though, we refrain. Mixing medications with alcohol is seldom a good idea. But listen: this warning applies to cannabis, too. Mixing medications with marijuana products can be detrimental to your health – especially if you aren’t being guided by a physician. As with anything involving cannabis use, all sorts of caveats abound. One is that there hasn’t been enough research conducted on the effects of cannabis by itself or with other products. This is largely because the U.S. government still considers cannabis to be dangerous and lists it as a Schedule 1 drug (same category as cocaine and heroin), which restricts funding for studies. Another is that, as with most drugs, cannabis can affect different people in different ways. The manner in which you consume cannabis also can vary its effects. Smokers, for example, are likely to feel something almost immediately, while those ingesting edibles or using oils may not experience a\ reaction for hours. Underlying all of the above is the fact that virtually all compounds interact with each other in ways that are sometimes negative. According to Anna Wilcox, a freelance writer whose specialty is health and wellness, drug interactions can be difficult to gauge. In an article titled “9 Prescription Medications You Should Avoid Mixing With Weed,” published on the website, Wilcox wrote, “Not only might two substances interact with each other, but they may also interact with whatever anomalies you may have going on with your personal biochemistry.” For the record, the prescription medications Wilcox lists belong to a number of different categories: drugs containing propoxyphene (an opioid painkiller), buprenorphine (another opioid) and levomethadyl acetate (a synthetic opioid), plus those classed as beta blockers (used to manage blood pressure, etc.), benzodiazepines (sedatives), SSRIs and SNRIs (antidepressants), antipsychotics (tranquilizers) and Sodium oxybate (an anti-sleep medication used to treat narcolepsy). Confusing trade names aside, the important point is this: negative compound interactions are more common than is generally known. As pointed out in a 2017 article on, a website that bills itself as “the world’s largest cannabis information source,” even caffeine has been shown to interact with 25 different drugs in ways that are classified as “moderately severe to severe.” Take the grapefruit. According to the U.S. Food and Drug Administration, grapefruit juice can cause problems with some statin drugs that lower cholesterol, some drugs that treat high blood pressure, some anti-anxiety drugs and even some antihistamines. Where, then, does that leave cannabis? Well, the news might not be as bad as it sounds. According to, “most potential interactions that have been identified are relatively mild. And, in fact, some drugs seem to work together with cannabis favorably.” Greg Carter, M.D., a physician at Spokane’s St. Luke’s Rehabilitation Institute, taught a continuing medical education class on medical marijuana for the Spokane Pharmacy Association. “There are not that many major drug interactions between cannabis and prescription drugs,” he said. The Mayo Clinic is more cautious, however, even as the noted health facility stresses that cannabis has been shown to help those suffering from certain conditions. Glaucoma, for example. Cannabis also helps reduce the nausea and pain of people undergoing cancer and HIV treatment. In addition, cannabis use might even work to reduce some muscle conditions related to multiple sclerosis. Yet, too, the Mayo Clinic supports Wilcox’s article, stating that, in addition to possibly increasing the effects of alcohol, cannabis interactions “might” reduce the effectiveness of medications aimed at blood-clotting, reducing anxiety, alleviating depression and even treating HIV. In particular, it seems drinking while consuming cannabis can lead to problems. A 2007 paper published in the American Journal of Health-System Pharmacy stated that mixing cannabis with alcohol can cause “central nervous system depression,” which can affect both breathing and heart rate and can result in a loss of consciousness. So the lesson here would seem to be clear: Be cautious when you use cannabis. Pay particular notice when you’re taking any kind of medication, prescribed or otherwise. As Carter of St. Luke’s said, “I do think it is very important for anyone using cannabis either medically or recreationally to let their health care provider know of that.” Or to quote writer Wilcox (the italics are hers), “The best advice? If you’re trying a new medication and decide to consume cannabis, listen to your body and talk to a doctor.” And do it before reaching into that medicine cabinet.
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