From the Guidelines
Marijuana use can have significant effects on blood pressure, and individuals with hypertension should exercise caution when using it, as it can cause an increase in blood pressure and heart rate shortly after use, followed by a decrease in blood pressure during prolonged use. The active compounds in marijuana, particularly THC, affect the cardiovascular system by binding to cannabinoid receptors that influence blood vessel dilation and heart rate 1. CBD, another compound in marijuana, may have different effects, and some research suggests it might help lower blood pressure, though evidence is limited 1.
Key Considerations
- Regular marijuana users may develop tolerance to these cardiovascular effects over time 1.
- If you're taking blood pressure medications like beta-blockers, ACE inhibitors, or calcium channel blockers, marijuana may interact with these drugs, potentially causing dangerous drops in blood pressure 1.
- Lifestyle modifications, such as weight reduction, reduction in sodium intake, and regular physical activity, can help manage blood pressure and reduce the risk of cardiovascular disease 1.
- Monitoring blood pressure regularly and starting with low doses of marijuana can help minimize potential risks 1.
Recommendations
- Individuals with hypertension should consult with their healthcare provider before using marijuana 1.
- Be aware of symptoms like dizziness or rapid heartbeat that could indicate problems when using marijuana while managing blood pressure 1.
- Follow established guidelines for lifestyle modifications to manage blood pressure, such as those outlined by the American Heart Association and the European Society of Cardiology 1.
From the Research
Marijuana and Blood Pressure
- The relationship between marijuana use and blood pressure is complex, with some studies suggesting an increase in blood pressure and others indicating a decrease 2, 3, 4.
- A study published in 2016 found that marijuana cigarettes cause increases in heart rate, supine systolic and diastolic blood pressures, and forearm blood flow via increased sympathetic nervous system activity 2.
- In contrast, a 2021 study found that cannabis use was associated with a reduction in 24-hours systolic and diastolic blood pressure values in older adults with hypertension, with a nadir at 3 hours after cannabis administration 4.
- Another study published in 2019 found that current marijuana users had a higher prevalence of elevated blood pressure, Stage 1 hypertension, and Stage 2 hypertension than never users, although the differences were only statistically significant for heavy users 3.
- The acute physiological effects of marijuana include a substantial dose-dependent increase in heart rate, generally associated with a mild increase in blood pressure, although orthostatic hypotension may occur acutely as a result of decreased vascular resistance 5.
Comparison with Other Medications
- A 2021 study compared the effectiveness and safety of beta-blockers, calcium channel blockers, and angiotensin receptor blockers in hypertensive patients, and found that all three medications had similar efficacy in reducing systolic and diastolic blood pressure 6.
- However, this study did not investigate the effects of marijuana on blood pressure, and more research is needed to fully understand the relationship between marijuana use and blood pressure 2, 3, 4, 5.
Key Findings
- Marijuana use may be associated with an increase in blood pressure, particularly in heavy users 2, 3.
- However, some studies suggest that marijuana use may also be associated with a decrease in blood pressure, particularly in older adults with hypertension 4.
- More research is needed to fully understand the relationship between marijuana use and blood pressure, and to determine the potential risks and benefits of marijuana use in different populations 2, 3, 4, 5.