Effects of Marijuana on Blood Pressure and Hypertension

Health > The NCSM

How marijuana effects high blood pressure is a frequent query for medicinal marijuana users who may be looking to improve their blood pressure.  Many need to know can marijuana lower blood pressure.  There are few direct double-blind, placebo controlled studies on the issue, but there is plentiful evidence about the effects of pot on cardiovascular measures.

Effects of Marijuana on Blood Pressure
Short-term EffectsLong-term effects
  1. Increased blood pressure
  2. Increased heart-rate
  3. Possible orthostatic intolerance (dizziness on standing)
  • Decreased blood pressure
  • Relaxation

Figure 1. Source: https://s-media-cache-ak0.pinimg.com/originals/56/e1/ac/56e1ac2ea6fa039ae7b9caa91de8372c.jpg

Is Marijuana Good For High Blood Pressure?

The affect of marijuana on blood pressure is, according to the evidence, a complex matter.  In the short-term, there is a transient rise in blood pressure and heart rate, akin to activities like exercise and sex.  During the period of an hour following use of bud, hash, and other forms of marijuana, there is an increase in the risk of cardiac events like heart attack and stroke, though the overall risk from marijuana alone is low.  This is the result of the stimulating affect of thc and other stimulating cannabinoids on the heart, brain, and cardiovascular system.

Smoked cannabis may raise the risk of heart attack by 4.8 times for the first hour after smoking.  In some cases, cannabis has been implicated in a rare condition called cannabis arteritis, although there have only been a handful of cases.  Arteritis is inflammation and lesions in the arteries leading to tissue necrosis.  There has only been less than 100 cases documented, so the connection to cannabis is not clear.  However, anyone who already has arteritis or Bueger’s disease which is linked most closely to cigarette smoking should closely monitor blood pressure when using medicinal cannabis.

In healthy people, a stimulus like exercise will cause an initial rise in blood pressure and heart rate.  Immediately after, there is an increased risk of cardiac events.  This is why someone who may be in great health will occasionally go into a cardiac arrest after running a marathon.  This is also why those with heart conditions are cautioned about sexual activity.  Heart rate will come back to normal in the minutes after the stimulus; however, this happens much slower in those with known or unknown cardiovascular conditions.  Heart rate and blood pressure may remain elevated for a longer period of time in these persons, leading to a longer period of increased risk of cardiac events from smoking marijuana.  A study done at Harvard Medical School reports that the risk of cardiac events increase 5 times after smoking marijuana, and returns to normal within 5 hours.  Risk could remain elevated if use continues, or conversely, tolerance may instead set in.

The increased risk of cardiac events is largely theoretical and has been extrapolated from animal studies, case reports, and meta-analysis that do not necessarily isolate marijuana use from other risk factors.  The few studies examining the risk such as the University of California CARDIA study found no long-term link between cannabis use and cardiovascular events.  Therefore, users who are concerned about adverse effects on bp should monitor their blood pressure and consult with their physicians about medicinal or recreational marijuana use if they have high blood pressure or other cardiovascular conditions.

Figure 2. source: https://static.mjwellness.com/uploads/news-editor-images/57f6009864506.jpg

Does Smoking Weed Lower Blood Pressure?

After the initial transient rise in blood pressure, which can rarely be dangerous, especially for those with other risk factors, blood pressure may subsequently decrease.  Once tolerance to the drug’s effects set in with repeated use, there may be a net decrease in blood pressure over time.  The initial hypotensive effect may even be experienced as dizziness upon standing a few minutes after smoking marijuana.  Some studies even demonstrate if marijuana is ingested in a standing position, the initial rise in blood pressure may be blunted or exterminated and one experiences only a drop in blood pressure.  Anandamide, the body’s natural form of thc, causes the blood vessels to relax, reducing arterial pressure.  However, when we examine the question does cannabis lower blood pressure, the picture is more complicated.  Although some components like CBD and anandamide may lower blood pressure, smoking the plant with the full range of cannabinoids will have different effects.  Therefore, different strains may have different effects on blood pressure.  Sativa strains are more stimulating and may lead to an initial rise in blood pressure.  Indica strains are more relaxing and may cause less increase in blood pressure and heart rate or may reduce blood pressure.  If one has concerns about one’s blood pressure, one should monitor blood pressure closely when using marijuana to make sure it doesn’t go to high and see if marijuana use subsequently lowers your blood pressure.  The answer will be different for different people.

Figure 3. source https://420evaluationsonline.com/files/articles/50341597b3d9ad4c99be5514e5ce374c2bkvnsksdfasdfasdfasdf.png

Can You Use Medical Marijuana For High Blood Pressure?

Over the long-term, it appears that marijuana might help lower blood pressure.  It appears to work like exercise.  Immediately after exercise there is a rise in blood pressure and a possibly slight increase in the chance of cardiac events.  However, following that initial period, there is a drop in blood pressure and an overall blood pressure reduction with exercise.  Cannabis seems to work similarly.  However, due to the lack of studies on the issue, care must be taken to monitor one’s own blood pressure to see what effect weed smoke or edibles have on oneself in particular.  One can also discover what effects different strains, sativa and indicas, have on your blood pressure.

Conclusion

The effects of marijuana on blood pressure is complex.  Acutely and for an hour or so after ingestion of marijuana, there is a slight rise in blood pressure and heart rate.  During the next hour, there is a slight rise in the risk of cardiac events similar to the increased risk from exercise.  Afterward, blood pressure may return to normal or may be reduced from baseline.  The best approach for those concerned about blood pressure is to take and record several blood pressure readings, before, immediately after, and several hours after smoking marijuana to make sure it isn’t causing high blood pressure or seeing what strains and patterns of intake  may help to lower blood pressure.

Comments
0
Leave a replay

Number of views: 12943