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Marijuana Can Cause These Awful Side Effects, According to Experts

Five side effects of marijuana to be aware of.
FACT CHECKED BY Emilia Paluszek

Medicinal marijuana is used to help treat symptoms of neurological and mental health conditions, pain, inflammation and many other health issues and although it's not legal yet in every state, it's become more widely accepted in the medical community in recent years. While marijuana has several benefits when used for medicinal purposes, it does affect everyone differently and there's side effects to be aware of. Before using marijuana, Rebecca Abraham RN BSN, a certified cannabis nurse with Acute on Chronic, a medical cannabis clinic and education company tells Eat This, Not That! Health, "Talk to your doctor or provider and disclose cannabis use (even CBD), or seek out a cannabis nurse or doctor.  Stay hydrated and don't mix cannabis and alcohol." Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Medication Interactions

Woman is holding a mobile phone and a bottle of pills

Abraham explains, "There are over 100 medications that interact with cannabis. Many of them can be managed by your medical team as long as the patient or the medical team has been educated in cannabis. CBD has more medication interactions than THC and both are metabolized in the cytochrome p-450 system in the liver. This is why it's important to tell your doctor or provider that you use CBD or cannabis. Oftentimes the drug interactions and the effects of cannabis and CBD allow the patient's provider to decrease doses of (or stop) other medications.  You should consult a healthcare professional before using cannabis if you take any prescriptions or supplements but especially if you take: Coumadin, Plavix, Tamoxifen, Xyrem, and some immunotherapies." 


Cannabis Hyperemesis Syndrome

Woman Suffering From Nausea

According to Abraham, "Cannabis Hyperemesis Syndrome is a side effect when the cannabis user vomits and dry heaves uncontrollably for hours that typically happens to chronic long-term cannabis users that consume large amounts of THC cannabis. Studies show younger recreational users seem to experience this phenomenon the most, Adult-use cannabis users are more at risk than medical users for this phenomenon. Tell tale signs of this syndrome include symptom relief with hot showers and vomiting and dry heaving subsiding with cessation of THC use. Patients experiencing Cannabis Hyperemesis Syndrome are at risk for dehydration, and electrolyte imbalances, and may require IV hydration. 



Thoughtful girl sitting on sill embracing knees looking at window, sad depressed teenager spending time alone at home, young upset pensive woman feeling lonely or frustrated thinking about problems

Abraham says, "Certain doses of cannabis can change what the substance can do. Too much THC can cause anxiety in many users. Every cannabis user's optimal dose for adult use or medical use is different and depends on their individual genetics, metabolism, tolerance, diet, medical history, supplements, and pharmaceuticals. Depending on how much THC is overconsumed, anxiety can range from mild discomfort to extreme discomfort with paranoia and hallucinations. This will resolve typically within 2-12 hours. This may cause a rapid heart rate in some users. Tachycardia caused by cannabis and anxiety can go as high as 150-170 with extreme overconsumption or mixing cannabis with alcohol or stimulants but should remain at a regular rhythm (AKA a normal steady beat) and resolve within 10-30 minutes. However, your heart rate may still remain elevated by 20-50% for a few hours. This is likely because of the flight or fight response being induced by cannabis. If this happens to you, take deep breaths, lie down, relax, watch or listen to something comfortable and familiar." 


Low Blood Pressure

man having blood pressure checked
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"Cannabis is a vasodilator (opens blood vessels up), this particular physiology is used in many antihypertensives to treat hypertension," Abraham states. "Cannabis can lower blood pressure (and cannabis may become a treatment in the future for hypertension) as seen in this study that followed patients for 3 months. Older patients, folks with orthostatic hypotension, POTS syndrome, patients with heart disease, patients on antihypertensives, or patients with liver disease should monitor their blood pressure when using cannabis and consult their doctor or provider prior to use.  Patients should monitor for signs of dizziness or fatigue, as these may be signs of low blood pressure. Older adults (65+) or folks with weakness or difficulty ambulating should get out of bed slowly when using cannabis and be sure their environment is safe to prevent falls. (Ex-Keep a cane or walker next to your bed, make sure rug corners are tucked in)." 


Eye and Mouth Dryness

Abraham shares, "Cannabis can lead to mild dehydration, dry eyes, and dry mouth. Folks that already have dry eyes and dry mouths, may experience more extreme side effects. Drinking water will help with dry mouth. Over-the-counter supplements like Biotin and Eye drops (saline/artificial tears) can help." And to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather