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. Call the ASPCA Animal Poison Control Center at (888) 426-4435. Did your pet eat chocolate, xylitol, or another potentially poisonous substance? A CDC report found that synthetic products sold as cannabidiol (CBD) had sickened dozens of users in the state, including so-called "Yolo CBD Oil."
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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.
Animal Poison Control
The ASPCA Animal Poison Control Center (APCC) is your best resource for any animal poison-related emergency, 24 hours a day, 365 days a year. If you think your pet may have ingested a potentially poisonous substance, call (888) 426-4435. A consultation fee may apply.
Are you a veterinarian or animal healthcare professional? See the APCC’s Veterinary Resources page for more information.
Our Poison Control experts have also provided valuable information below to help parents recognize and protect their pets from poisonous substances including plants, human foods, human medications and more.
Poison Control experts set the record straight on the safety risks of a variety of household substances.
For additional animal poison control information, listen to monthly podcasts from APCC experts below.
Fake CBD Poisoned At Least 52 People In Utah Last Winter, Officials Say
According to the Centers for Disease Control (CDC), synthetic products marketed as cannabidiol (CBD) sickened at least 52 people in Utah last winter, sending 31 of them to emergency rooms.
This week, the agency released a report on a poisoning outbreak that occurred in the state between December 2017 and January 2018, and which it linked to one or more synthetic cannabinoids being sold as the genuine article. Users reported that they had purchased such products as “Yolo CBD oil” at regular smoking and/or head shops, or acquired them from friends.
Unlike the many poisoning victims of K2 and other chemicals sold as ‘synthetic marijuana’ (a.k.a. synthetic cannabinoids), all of the patients identified in the report believed they were consuming legally derived CBD, which experts maintain has little to no potential for psychoactive effects. The cannabinoid chemical is found in varying amounts in both marijuana and hemp, and has been shown to have significant potential applications (and some outright proven ones) in medicine.
As CBD’s reputation in certain areas has grown, many new users have sought out the chemical for an effective but benign way to help with pain, anxiety, or recovery from substance abuse, among other things.
Over the past several years, however, a growing range of unregulated products claiming to contain CBD have also been flooding state and national marketplaces, putting consumers at risk of wasting their money, or worse. Last year, the U.S. Food and Drug Administration moved to crack down on four CBD manufacturers and distributors, particularly focusing on the companies’ claims around cancer treatment.
The market surge on so-called CBD has also meant that would-be safe users of effective, actual cannabidiol are finding they need to do a lot of time-consuming research about each product (and often still cross their fingers) before swallowing companies’ claims.
Eliezer, a 38 year old homeless heroin addict, smokes a K2 cigarette in the Bronx on May 4, 2018 in . [+] New York City. Eliezer often snorts his heroin instead of injecting as he feels it lessens the chances of overdosing on the drug. The Bronx was the borough with the highest number of overdose deaths in 2016 with 308 residents dying. (Credit: Spencer Platt/Getty Images)
In Utah, the CDC reported, “By the end of January 2018, suspected cases [of synthetic cannabinoid poisoning] were identified in 52 persons. Nine product samples (including one unopened product purchased by investigators from a store and brand reported by a patient) were found to contain a synthetic cannabinoid, 4-cyano CUMYL-BUTINACA (4-CCB), but no CBD.”
Roberta Horth, an officer with the CDC’s Epidemic Intelligence Service, and the report’s lead author, pointed out for Gizmodo that the range of easily tweak-able synthetic cannabinoids available in recent years seem to pose significantly more (and more unexpected) risks so far than organic cannabinoids such as THC, which can also produce negative psychological and physical side effects. She also noted that fatalities following the use of this particular formulation, 4-CCB, have already been reported in Europe.
Among the 52 people the CDC was able to identify as being part of the outbreak, t he top three symptoms experienced were altered mental status, nausea or vomiting, and seizures or shaking — symptoms or side effects which have not been linked to CBD, incidentally, but which CBD has been variously used to treat.
Regarding the recent Utah poisonings, the CDC report continued,
Eight of the tested products were branded as ‘Yolo CBD oil’ and indicated no information about the manufacturer or ingredients. Blood samples from four of five persons were positive for 4-CCB. Press releases were distributed to media outlets December 19–21, 2017, with a warning regarding the dangers of using the counterfeit product . The number of reported cases peaked during this outreach and dropped shortly thereafter.
Thirty-four suspected cases were reclassified as confirmed if the person reported use of a Yolo product or laboratory testing found 4-CCB. Approximately one quarter of persons were aged
Rapid identification and a coordinated response among state and local agencies contributed to control of the outbreak. This investigation highlights the hazards of consuming unregulated products labeled as CBD. States could consider regulating products labeled as CBD and establishing surveillance systems for illness associated with products labeled as CBD to minimize the risk for recurrences of this emerging public health threat.