Cannabis as Health Hazard

"In our patient's case, likely the cardiovascular event came during sudden and unexpected strain on the body with hallucinations."
"Often times people keep eating -- or sucking on the sucker in this case -- until they start to feel some relief, or feel something."
"I don't know about you, but I know that when I eat a sucker I don't lick it and put it away. Maybe that's not the best delivery [of cannabis] method."
Dr. Alexandra Saunders, chief resident, Internal Medicine, Dalhousie University, Halifax, Nova Scotia

"That drug in that dosage was not something that his body was ready for."
"We're going to have people that have never tried marijuana before, or who have not tried it in years [running into medical problems]."
"I think we need to be ready for more cardiac complications presenting to our emergency departments."
Dr. Robert Stevenson, cardiologist, New Brunswick Heart Centre

A 70-year-old man bought a marijuana lollipop containing 90 mg of THC, the psychoactive component of pot. A typical joint contains about seven mg.    Robyn Beck / AFP

Drs. Saunders and Stevenson, co-wrote a report published in the Canadian Journal of Cardiology, which they titled "Marijuana Lollipop-Induced Myocardial Infarction". The patient upon whose experience they based their report, a 70-year-old man from Saint John, New Brunswick had a history of heart disease. That history was extensive enough to include triple bypass surgery, yet his condition had been stable over the past two years.

Because the man also suffers from arthritic joints, he took the advice of a friend who recommended that marijuana would help relieve his pain and allow him to sleep better at night. He decided on a marijuana lollipop, knowing nothing about its properties and taking it on faith that it might indeed solve his sleep problems. That lollipop contained 90 mg of THC, the psychoactive compound in pot. In comparison, a typical marijuana cigarette contains about 7 mg of THC.

Had the man understood that a few licks of the lollipop would have been more than sufficient to give his experiment a try, he would never have gone so far as to eat almost the entire candy infused with THC. But he did, and after a half-hour began experiencing dreadful hallucinations of "impending doom", along with crushing chest pains. On arrival at the emergency department of a hospital, blood work and a cardiogram indicated heart attack signs.

The man was duly treated. Once the effects of the THC had worn away, his hallucinations ceased, and the pain in his chest ended. Dr. Saunders then launched an Internet search of marijuana dispensaries in the near region, discovering finally how much psychoactive THC the sucker had contained. A later scan on the patient indicated damage to the heart muscle had occurred; less blood leaving his heart with each contraction. 

While recreational marijuana is now legal in Canada, pot-laced edibles are not yet legal. The use of cannabis is becoming increasingly popular with middle-aged and older Canadians; these are baby boomers entering the time of their lives when they become more at risk for heart disease. Some of them may have used marijuana in their youth, many others never did, but cannabis may seem somewhat appealing to them to assuage the pain or discomfort of their aging body.

Dr. Neal Benowitz, chief of clinical pharmacology at the University of California, San Francisco in a related editorial with the publication of the report in the Canadian Journal of Cardiology, wrote that the heart can be strained by THC in stimulation of the sympathetic nervous system which causes the heart to work harder. As heart rate and blood pressure increase, oxygen demand rises and the body produces a surge of hormones that can constrict coronary vessels.

Furthermore, THC can also cause anxiety, hallucinations, paranoia and panic and for some people while a few puffs of pot before bed help with sleep "in which case toxicity is likely to be low", when smoked or vaped, THC is rapidly absorbed into the bloodstream, travelling to the brain where the effects are almost immediate, making it easier to dose. In the instance of edibles, absorption is "slow and erratic", said Dr. Benowitz --where THC levels peak at four hours or so.

Edibles are sold without adequate information, making it difficult for people to figure out what an appropriate dose might represent, so they can end up consuming more than intended, before effects are felt. In the instance of the 70-year-old man, three-quarters of the lollipop was consumed, representing 70 mg of THC, where the maximum recommended daily dose is no more than 20 mg of THC.

Leading Dr. Benowitz to recommend CBD rather than THC to help with pain and invite uninterrupted sleep, since CBD doesn't have THC's mind-altering effects.
"The legalization of cannabis has significant public support but also raises public health problems. Some users may benefit from the social and medical effects, but others will be at risk for adverse health problems. Little information has spread to patients or caregivers about cannabis use in elderly patients, and especially those with cardiac disease. For better or worse, give advice and care to those patients using cannabis now needed to provide optimal healthcare to these patients."