The term "marijuana" typically refers to the tobacco-like preparations of the leaves and flowers of the plant cannabis sativa and cannabis indica. The plant contains many psychoactive compounds, often referred to as cannabinoids. The primary psychoactive ingredient is believed to be tetrahydrocannabinol, which is also responsible for most of the intoxicating effects experienced by users. Different preparations of marijuana vary in strength, with THC concentration in cannabis varying with climate, soil, and cultivation techniques. Also, the amount absorbed by the body varies with the route of administration. The effects of cannabis depend on various things: the dose, mode of administration, user’s prior experience with the drug, user’s expectations/attitudes towards the drugs, and social environment when using the drug. Cannabidiol (CBD) is one of the most studied compounds of the cannabis plant. CBD drew attention when it was shown to stop seizures in a group of patients with a form of epilepsy that does not respond to conventional therapies. Potential benefits of CBD might include anti-inflammatory, immune system, and anti-anxiety effects. A great deal more scientific investigation is needed.
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StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-.
Anisha R. Turner ; Benjamin C. Spurling ; Suneil Agrawal .
Last Update: May 15, 2022 .
Continuing Education Activity
The term “marijuana” typically refers to the tobacco-like preparations of the leaves and flowers of the plant cannabis sativa. The active ingredient is believed to be tetrahydrocannabinol (THC), which is also responsible for intoxication. Different preparations of marijuana vary in strength. THC concentrations vary with climate, soil, and cultivation techniques. Additionally, THC absorption varies with the route of administration. This activity reviews the pathophysiology, diagnosis, and management of marijuana toxicity and highlights the role of the interprofessional team in caring for affected patients.
Summarize interprofessional team strategies for improving care coordination and communication to advance the prevention and treatment of marijuana toxicity and improve outcomes.
The term “marijuana” typically refers to the tobacco-like preparations of the leaves and flowers of the plant cannabis sativa and cannabis indica. The plant contains many psychoactive compounds, often referred to as cannabinoids. The primary psychoactive ingredient is believed to be tetrahydrocannabinol, which is also responsible for most of the intoxicating effects experienced by users. Different preparations of marijuana vary in strength, with THC concentration in cannabis varying with climate, soil, and cultivation techniques. Also, the amount absorbed by the body varies with the route of administration. The effects of cannabis depend on various things: the dose, mode of administration, user’s prior experience with the drug, user’s expectations/attitudes towards the drugs, and social environment when using the drug.
Marijuana intoxication is dose-related and has multiple names depending on the preparation: grass, ganja, hashish, etc. The amount absorbed by the body varies by the route of administration and concentration of the source being used, which can vary widely. Marijuana is commonly smoked or vaporized due to the rapid onset of symptoms, but marijuana can also be eaten (i.e., “grass” brownies) or drank (i.e., marijuana tea or marijuana tincture). Smoked marijuana has an increased potency, quoted as high as 2.6 times by some sources. Marijuana is used for both recreational and therapeutic purposes. Although some people promote the “harmless” nature of marijuana, acute and chronic intoxication can occur.
According to the World Health Organization (WHO), marijuana is the world’s most widely cultivated, trafficked, and abused illicit substance. Approximately 2.5% of the world’s population (147 million people) uses it. Its use is more prevalent among men than women—a gender gap that widened in the years 2007 to 2014. Use is widespread in the adolescent and young adult population. According to the Monitoring the Future survey, an annual survey of drug use in America’s middle and high school students, rates of use within one year ranged from approximately 9% in 8 graders to 35% in 12 graders. In the United States, cannabis is still a Schedule 1, meaning it is not scheduled for federal medical use and has a high potential for abuse.
History and Physical
The initial state of acute intoxication formulates recreational users’ symptoms: euphoria, perception alterations such as time and spatial distortion, intensification of ordinary sensory experiences, and motor impairment. Not all effects of cannabis intoxication are welcomed by users, as some experience unpleasant psychological reactions such as panic, fear, or depression. Acute intoxication also affects the heart and vascular system, resulting in cannabis-induced tachycardia and postural hypotension. CNS and respiratory depression have been noted with high doses in animal models. Studies show that inhaled doses of 2 to 3 mg of THC and ingested doses of 5 to 20 mg THC can cause impairment of attention, memory, executive functioning, and short-term memory. Doses > 7.5 mg/m2 inhaled in adults and oral doses from 5 to 300 mg in pediatrics can produce more severe symptoms such as hypotension, panic, anxiety, myoclonic jerking/hyperkinesis, delirium, respiratory depression, and ataxia. Conjunctivitis is a consistent physical exam finding regardless of the route of administration. In children, neurological abnormalities such as lethargy and hyperkinesis can be signs of life-threatening toxicity. Although acute toxicity is uncommon in non-pediatric patients, those who come to medical attention are more likely to have hyperemesis, behavioral problems, or a medical emergency such as bronchospasm due to inhalation. There is disagreement about how long these impairments persist after taking cannabis, ranging from hours to days. Chronic use may lead to long-term effects on cognitive performance, “amotivational syndrome” (loss of energy and a will to work), and respiratory disorders. There have also been various reports of patients presenting with cyclic vomiting syndrome/cannabinoid hyperemesis. Cannabis intoxication can lead to acute psychosis in many individuals and can produce short-term exacerbations of pre-existing psychotic diseases such as schizophrenia. Psychiatric symptoms observed in some studies include depersonalization, fear of dying, irrational panic, and paranoid ideas.
The standard urine drug screen can be used to detect THC metabolites, primarily THC carboxylase. The lower limits range from 20 to 100 ng/mL. Second-hand exposure causing positive results is tough to achieve in adolescents and adults, although this has not been studied in children. Reported false positives for THC include dronabinol, efavirenz, PPIs, hemp seed oil, NSAIDs, and baby wash products in infants. Although, false positives are significantly less likely in testing laboratories with gas chromatography capabilities. Positive results for THC carboxylase have been reported up to 10 days after weekly use and up to 30 days after heavy daily use, making the timeline of exposure different and the severity of intoxication difficult to correlate.
Although less commonly used, other ways of detecting marijuana use are available. This includes detecting THC carboxylase in hair, which has the benefit of detection up to 3 months after use but often will not become positive until several weeks after use has been initiated. Detection of THC can also be accomplished in the oral fluid within 24 hours of use and in blood within about 14 to 21 days of use. Breathalyzer tests have also been proposed, but since small amounts of cannabis continue to be released from fat into the blood long after short-term impairment wears off, this method has not been promoted.
Treatment / Management
Most adolescents and adults do not warrant testing for the diagnosis or treatment of cannabis intoxication. However, if chest pain is present, it is reasonable to obtain a 12-lead electrocardiogram and possibly cardiac markers to assess myocardial ischemia or infarction. There is thought to be an elevated risk up to 4.8 times for MI within 1 hour of marijuana use. Patients with toxic ingestion should also be screened for co-ingestion, especially if electrolyte abnormalities or OTc or QRS prolongation is noted on EKG. Some patients, particularly children, may require further testing if exposure is unknown, including rapid blood glucose, electrolytes, blood gas analysis, and neuroimaging (e.g., computed tomography of the head). Neuroimaging should be avoided in known cannabis exposures unless focal neurologic findings are also present or concerns for other etiologies such as head trauma exist.
The treatment for marijuana intoxication is symptomatic management. The extent of management has numerous factors, including the age of the individual and the amount of cannabis ingested. Several cases of accidental cannabis poisoning in geriatric patients have resulted in intensive care admissions due to central nervous system depression. Unintentional ingestion by children has also resulted in similar admissions. In cannabis-induced psychotic disorders, safe cannabis detoxication typically requires 24 hours but sometimes longer if persistent psychosis or unstable vital signs occur.
CBD Products Do They Work?
Cannabidiol (CBD) is one of the most studied compounds of the cannabis plant. CBD drew attention when it was shown to stop seizures in a group of patients with a form of epilepsy that does not respond to conventional therapies. Potential benefits of CBD might include anti-inflammatory, immune system, and anti-anxiety effects. A great deal more scientific investigation is needed.
The Full Story
There is a term of Greek origin, panacea, that means all-healing. Vitamin D, magnesium, turmeric, and recently cannabidiol (CBD) are some of the products that have enjoyed time in the public eye as the panacea we are all missing. CBD is a chemical compound from the cannabis plant. CBD is not tetrahyrdrocannabinol (THC), which is the main psychoactive substance in cannabis that causes intoxication and is potentially habit forming.
The idea that the cure lies in plants and natural medicine is alluring. After all, humans have relied upon natural medicines much longer than tightly-controlled pharmaceuticals. When drugs are created, a common method is to find a receptor in the body and make a compound to act on that receptor. Cannabinoid-sensitive receptors exist in our bodies (primarily in the central nervous and immune systems), and the cannabinoids that act on them already exist in abundance in the cannabis plant.
CBD does not cause people to become intoxicated or “high” and, so far, has not been shown to be addictive like THC. Cannabis plants today have been cultivated to contain high levels of THC. Hemp plants are cannabis plants that have been cultivated to have low amounts of THC (although not zero) and higher amounts of CBD. Hemp plants are the source of the flood of CBD products on the market, from skincare to latte add-ins.
In America, hemp plants are now legal to grow. However, extracted CBD from hemp plants is a pharmaceutical ingredient according to the United States Food and Drug Administration (FDA). Because of this, CBD cannot be sold or marketed as a dietary supplement or food in the United States. However, Epidiolex, an FDA-approved, prescription CBD medication is available and has been shown to help some people with rare types of epilepsy that are not controlled by other medications.
Supplements and non-pharmaceutical CBD products are not regulated by the FDA. This means that there is no oversight from the FDA assuring that these products are made in an appropriate environment, are free from contamination, or even contain what they advertise on the label. This has become an important issue in major sports where athletes take supplements or try to use natural products instead of pharmaceuticals. There have been cases in which athletes used CBD products and, during drug screens, tested positive for THC. It might be that the athletes were not telling the truth, or it might be that they unknowingly used an unregulated CBD product contaminated with THC. Because of the lack of FDA regulation, CBD products may be contaminated with THC or other chemicals such as pesticides or heavy metals. In one study from 2017, an analysis of 48 CBD products revealed that less than one-third of the products had accurate labeling about their CBD concentration, and 21% contained THC. People who use CBD products should know that these products may contain potentially dangerous ingredients that can have negative or unwanted medical and legal consequences.
Much of the research on CBD has searched for anti-inflammatory and targeted immune system effects. Steroids are the most commonly used anti-inflammatory agents, but a steroid substitute could be very helpful, because steroids have extensive side effects. However, there are many inflammatory diseases for which chronic steroid therapy is one of the only effective treatments.
Common side effects reported from swallowing CBD products are generally mild and may be related to other components or contaminants present in the product. Drowsiness is the most common side effect, and decreased appetite, nausea, and diarrhea can also occur. Contamination with myrecene, another chemical found in in both cannabis and hemp, may be responsible for some of the sedating effects of CBD. CBD is metabolized by a major enzyme system in the liver and can have drug interactions. In animal studies, chronic CBD use also suppressed male fertility.
Research is ongoing, so more compounds of interest from the cannabis plant are sure to follow. But there are many unanswered questions. Can individual chemicals such as CBD alone provide a benefit, or is the entire plant needed (entourage effect) to realize the full effects? Additionally, studies on safety and use in children need to be pursued. Will CBD users develop tolerance and potentially experience withdrawal? These questions will not be answered until large groups of people taking CBD have been studied.
For now, there is no panacea.
If you are worried about a CBD exposure, check the webPOISONCONTROL ® online tool for guidance or call Poison Control at 1-800-222-1222. Whether you log on or call, expert assistance is available 24 hours a day.
Pela Soto, PharmD, BSHS, BS
Certified Specialist in Poison Information
Call 1-800-222-1222 or
- Over-the-counter CBD products (topical, oral, or otherwise) have not been studied in children and should not be used by children or adolescents.
- Tell your doctor about any strange or unwanted side effects that occur after use of CBD products.
- Ask your pharmacist to check for drug interactions involving regular medications and CBD-containing products.
This Really Happened
A 13-year-old boy was feeling anxious at school. A friend offered him a gummy thought to contain CBD. He went to the school nurse who called the boy’s parents and Poison Control. Poison Control indicated that if it truly was CBD alone, the boy should have no significant symptoms beyond mild sedation or dizziness. With increasing availability of THC-containing products, the school nurse was also informed of symptoms that would be expected with THC in his age group including excitation (anxiety, paranoia) and sedation. When Poison Control followed up on the boy several hours later, he had confessed that the ingestion was actually several days previously and that he had no effects. He was nervous about the exposure and wanted to be sure he was okay.