The query investigates if marijuana use results in increased bleeding.

Cannabis use and blood clotting: an exploration

Cannabis, a commonly used substance, has been associated with various health effects, including its potential impact on bleeding risks. Here's a breakdown of the current evidence surrounding this topic.

Firstly, it's important to note that no evidence supports an increased risk of excessive bleeding in most casual, infrequent, or low-dose users of cannabis [1]. However, the situation may be different for regular users or those consuming high doses.

Research has suggested that cannabis can act as a mild blood thinner, primarily through inhibition of the liver enzyme CYP2C9. This mechanism can increase bleeding risk, particularly when combined with blood-thinning medications like warfarin [1][3]. Such an interaction may lead to elevated warfarin levels in the blood, heightening the risk of excess bleeding.

Although direct clinical reports linking cannabis to bleeding during or after surgery are limited, the theoretical risk is significant enough that caution is advised before surgical procedures, particularly when patients use anticoagulants concurrently with cannabis.

Additional cardiovascular concerns linked with cannabis use — such as increased risk of arrhythmias, heart attacks, and stroke — further underscore the importance of careful medical evaluation before surgery or when on blood thinners [2][4].

Cannabis use is also associated with increased risks of acute ischemic stroke and aneurysmal subarachnoid hemorrhage (aSAH) in young people [1]. Moreover, it may increase the risk of rare bleeding disorders in the lungs and brain [1]. Cannabis use may also increase the chance of a life-threatening complication called delayed cerebral ischemia (DCI) after an event like aSAH [1].

Doctors may caution cannabis users to limit or restrict use ahead of heart surgery due to these potential complications [5]. Research has also found connections between cannabis use and rare complications of stroke and lung bleeding disorders [6].

When it comes to menstrual health, smoking cannabis might influence the length of the luteal phase in the menstrual cycle, leading to a shorter luteal phase compared to non-users [7]. However, no reliable research has explored the intensity, regularity, or frequency of menstrual bleeding during a female period due to cannabis use [8].

It's crucial to remember that these findings are based on current research and may not fully capture all potential risks or benefits of cannabis use. As such, it's always advisable to consult with a healthcare provider for personalised advice.

In summary:

Cannabis inhibits CYP2C9 enzyme, affecting metabolism of drugs like warfarin, increasing anticoagulant blood levels and bleeding risk [1][3].
Clinical data specifically on cannabis-related excess bleeding during surgery are limited, but potential interaction warrants caution.
Cannabis use is associated with increased cardiovascular risks, which could complicate bleeding management in surgical or anticoagulated patients [2][4].

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6146376/ [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6273049/ [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6330989/ [4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6273049/ [5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6330989/ [6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6330989/ [7] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6341549/ [8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6341549/