Medical marijuana is becoming more popular for treating long-term pain caused by illnesses like cancer, arthritis, and nerve problems.
But a new study from Gentofte University Hospital in Denmark suggests there may be a small risk to the heart when using this treatment.
The researchers looked at medical records from 1.6 million people in Denmark who were being treated for chronic pain. Out of these, about 4,600 people had filled at least one prescription for medical cannabis. The team wanted to see whether using this drug affected
the chance of getting an irregular heartbeat, a condition known as arrhythmia.
They found that people who took medical marijuana were 64% more likely to develop an arrhythmia within six months of their first prescription compared to people who didn’t use the drug.
This sounds like a big jump, but the actual number of people affected was small. Only 0.9% of medical marijuana users had an arrhythmia, compared to 0.5% of those who didn’t take it.
In Denmark, medical marijuana is allowed in three forms. These include CBD oils and sprays, herbal teas that mix THC and CBD, and dronabinol, which is a lab-made version of THC. All three types were studied, and the risk of arrhythmia was similar for each.
The study didn’t explain exactly why cannabis might raise the risk of heart rhythm problems. However, scientists already know that chemicals in marijuana, like THC and CBD, can affect the heart. They may change heart rate and blood pressure or affect how the blood clots. These changes might lead to irregular heartbeats.
Arrhythmias can be harmless in some people, but in others, they may cause serious health issues like stroke or heart failure. This study did not identify what types of arrhythmias occurred, so we don’t yet know how dangerous they were.
Another thing to think about is the role of pain itself. Chronic pain puts a lot of stress on the body and can also affect the heart. Many of the people who took medical marijuana were also using strong painkillers like opioids, which might also raise the risk of heart problems. So, it’s possible that the heart rhythm issues were not caused by cannabis alone.
Even though the overall risk is small, the study raises important questions. As more people use marijuana for medical or recreational reasons, it’s important to understand all its possible effects.
For people with heart conditions, it’s especially important to talk to a doctor before starting medical cannabis. Patients should also be checked for any heart-related side effects while using the drug.
This study is an important reminder that even medications meant to help can have side effects. More research is needed to better understand how marijuana affects the heart and to find out whether the risk of arrhythmia is linked to specific types of cannabis or other health issues.
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