Each week, we identify one top search term, speculate about what caused its popularity, and provide an infographic on a related condition. If you have thoughts about what’s trending and why, feel free to share them with us on Twitter or Facebook.
New research on cannabis and heart health, as well as increased use of a particular form of the drug, helped to make it this week’s top trending clinical topic. According to the World Health Organization, nearly 150 million people (2.5% of the world’s population) consume cannabis each year. This explains the interest in two recent studies that examined the relationship between its use and cardiac concerns.
A study published in JACC: Cardiovascular Imaging found that regular recreational use of cannabis is associated with potentially adverse features of left ventricular size and subclinical impairment of left ventricular function. Use in the past, however, was not associated with such features, which suggests that these effects may not be permanent. The study included nearly 3500 participants. Compared with individuals who had never or rarely used cannabis, after controlling for age, sex, body mass index, systolic blood pressure, use of cholesterol medication, diabetes, smoking, and alcohol consumption, regular use was associated with:
Larger indexed left ventricular end-diastolic volume
Larger end-systolic volume
Impaired global circumferential strain
Because of concerns like these, the authors of a new review article published in the Journal of American College of Cardiology call for “routine screening for marijuana use” in order to clarify the cardiovascular safety profile of the drug. Observational studies have suggested an association between marijuana use and a broad range of cardiovascular risks, such as myocardial infarction, arrhythmias, and cerebrovascular events, but more evidence is needed to properly clarify these associations. Concerns have also been raised about the possible interaction of cannabidiol (CBD) and commonly used cardiovascular drugs .
CBD is becoming increasingly popular, with a recent Medscape poll showing that nearly half of respondents are concerned or very concerned about their patients using unregulated CBD products. Only around a third (35%), however, indicated that they often or always ask patients about CBD use. More than half (55%) of the poll takers reported that they believe CBD to have medical benefits.
As cannabis use becomes more mainstream, researchers and medical professionals will continue to keep a close watch on its various effects on health, like the ones that resulted in the drug becoming this week’s top trending clinical topic.
Medical marijuana is any part of the marijuana plant that you use to treat health problems. People use it to get relief from their symptoms, not to try to get high.
Most marijuana that’s sold legally as medicine has the same ingredients as the kind that people use for pleasure. But some medical marijuana is specially grown to have less of the chemicals that cause feelings of euphoria.
Marijuana plants have multiple chemicals, known as cannabinoids. The two main ones are THC and CBD. THC gives some of the pleasurable effects that pot smokers are looking for, but it also has some effects that may treat medical problems.
Some research suggests that CBD may be helpful for some health issues, but it doesn’t cause you to get high.
People who smoke marijuana begin to feel its effects almost immediately, while those who eat it may not feel it for up to an hour.
When you smoke pot, THC goes from your lungs to the bloodstream and causes your brain cells to release the chemical dopamine, leaving you feeling high.
Experts know less about how CBD works. They think it may work sometimes with THC, and sometimes on its own, to have an effect on the brain.
Medical marijuana may help ease pain, nausea, and loss of appetite in people who have cancer and HIV. There’s not a lot of research on these areas yet, though.
Some research suggests medical marijuana may cut down seizures in people with epilepsy. Some studies show it also may ease multiple sclerosis symptoms like muscle stiffness and spasms, pain, and frequent urination.
Medical marijuana can change your mood, making you feel happy, relaxed, sleepy, or anxious. It can also disrupt your short-term memory and decision-making ability. These side effects can last 1 to 3 hours.
Large doses of medical marijuana can make some people have hallucinations, delusions, and paranoia. Research suggests that smoking marijuana can make breathing problems, like bronchitis, worse.
Regular smokers of medical marijuana may get respiratory problems, such as a daily cough and a higher risk of lung infections.
Studies also link routine use to mental illness, depression, anxiety, less motivation, and suicidal thoughts among young people. Marijuana use during pregnancy can raise the risk of health problems in babies. Marijuana use can result in addiction.
The FDA has approved two drugs that include ingredients also found in marijuana. Dronabinol has synthetic THC and is used to treat nausea from chemotherapy and extreme weight loss in people with AIDS.
Nabilone is used for the same reasons, but it has a man-made chemical that’s similar to THC.
Users smoke medical marijuana in paper-rolled cigarettes or pipes. You can also brew it into a beverage, eat it in cooked foods, or take it in pill form. The effects of a marijuana pill can be strong and long-lasting. This makes it hard to predict how it will affect a person. It can also be inhaled through vaporizers. Cannabinoid receptors have also been found in skin. Some use topical marijuana for pain and inflammation. More research is needed.
California voters were the first to legalize medical marijuana, in 1996. It’s now legal in almost half of U.S. states.
If you live in a state where it’s legal and your doctor has OK’d it, you can buy it from an authorized seller known as a dispensary. Some people may legally grow their own medical marijuana.
Some studies suggest medical marijuana may help relieve seizures in children with hard-to-treat epilepsy.
A type of medical marijuana known as “Charlotte’s Web” may help kids without getting them high, because the strain has very little THC.
(1) Anthony Souffle/Chicago Tribune/MCT via Getty Images
(2) FREDERIC J. BROWN/AFP/GettyImages
(3) Roger Harris / Science Source and Thinkstock
(4) Gordon Chibroski/Portland Press Herald via Getty Images
(5) Gabe Souza/Portland Press Herald via Getty Images
(6) The Image Bank
(8) Bob Berg/Getty Images
(9) Colin Robertson / Moment
(10) Keith Myers/Kansas City Star/MCT via Getty Images
Epilepsy Foundation Colorado: “The Use of Medical Marijuana for the Treatment of Epilepsy.”
Harvard Mental Health Letter: “Medical Marijuana and the Mind.”
Maa, E. Epilepsia, May 22, 2014.
Michael Kahn, president and founder, Massachusetts Cannabis Research Labs.
National Conference of State Legislatures: “State of medical Marijuana Laws.”
National Institute on Drug Abuse: “Drug Facts: Is Marijuana Medicine?”
“Drug Facts: Marijuana,” “How Does Marijuana Produce Its Effects?”
“How Does Marijuana Use Affect Your Brain and Body?”
ProCon.org: “22 Legal Medical Marijuana States and DC”
National Institutes of Health: “Distribution of cannabinoid receptor 1 (CB1) and 2 (CB2) on sensory nerve fibers and adnexal structures in human skin.”
U.S. National Library of Medicine: “Dronabinol,” “Nabilone.”
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional medical advice, diagnosis or treatment and should not be relied on to make decisions about your health. Never ignore professional medical advice in seeking treatment because of something you have read on the WebMD Site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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