Colorado just completed its first year of legalized recreational marijuana sales, and as more states pass legislation to allow possession of small amounts of marijuana, physicians are discovering the medical effects of these laws.
“There is a lot of rhetoric from both sides of the argument around marijuana use, but clinicians have a responsibility to look at it in an unbiased way. There are some benefits and some risks,” said Andrew A. Monte, MD, an emergency medicine physician at the University of Colorado, Aurora, and the Rocky Mountain Poison and Drug Center in Denver.
In February, the Colorado Marijuana Enforcement Division released its first annual report on the retail sale of marijuana. The report showed that about 150,000 pounds of marijuana plants and almost 5 million edible marijuana products were sold in the state in 2014, despite the drug still being classified as a Schedule I controlled substance by the federal government.
In the health care system, Dr. Monte said this has led to positive and negative changes, from a greater willingness among patients to disclose use of marijuana to increased exacerbations of chronic medical conditions, such as bronchitis, and higher rates of some acute medical problems.
Of the 2,000 patients seen each week in the University of Colorado emergency department, 1 to 2 will present with marijuana intoxication, while another 10 to 15 have marijuana-related illnesses, Dr. Monte reported in the Jan. 20 Journal of the American Medical Association (JAMA).
The symptoms of intoxication may include paranoia, tachycardia, hypertension, memory loss, or flushing, noted Jason Persoff, MD, an assistant professor of medicine and a nocturnist at the University of Colorado.
Although the legalization of recreational marijuana has not had a huge effect on his day-to-day practice, he is seeing some changes.
“In the past, marijuana was mostly smoked it seemed, but now marijuana can be ingested orally with the variety of edibles that are available,” Dr. Persoff said. “The difference between inhaled and swallowed marijuana is the half-life; the toxicity of smoked marijuana is about 2 to 4 hours, but ingested, it can last 6 to 8 hours.”
Most cases of marijuana intoxication seem to occur in novice users who may not understand the dose of marijuana they are ingesting with edibles, Dr. Monte said.
“A gummy bear or small chewable might have 10 mg of THC [tetrahydrocannabinol], whereas something larger like a candy bar might have as much as 60 mg or 100 mg,” said Jonathan P. Savage, DO, an emergency physician in Aurora, Colo.
The state's recommended dose for edibles is 10 mg, but, as Dr. Savage noted, most people would not think twice about eating an entire candy bar, thereby ingesting a large dose of THC.
In response to this problem, in February, Colorado put into effect a series of emergency rules requiring that edibles be packaged in single-serving, child-resistant containers and include no more than 10 mg of THC. Products can be bundled together, but the entire package cannot exceed 100 mg of THC.
The good news is that many cases of marijuana intoxication can be treated in the emergency department, with patients released within 12 hours. Most patients who presented with marijuana intoxication will be discharged with reassurance, according to Dr. Monte.
“If a patient presents with significant tachycardia or anxiety, we may give IV fluids or benzodiazepines, but this is relatively infrequent,” he said.
Other marijuana-related problems may take longer to resolve. Cannabinoid hyperemesis syndrome, a subset of cyclic vomiting syndrome, is more commonly seen among highly habituated, long-term users, Dr. Persoff said.
Patients with cannabinoid hyperemesis syndrome in the hyperemetic phase will present with recurrent stomach pain and cyclic episodes of nausea or vomiting.
Cyclic vomiting presentations increased from 41 per 113,262 ED visits to 87 per 125,095 ED visits after medical marijuana liberalization, according to data from 2 Denver-area hospitals that Dr. Monte reported in his JAMA viewpoint. And Dr. Savage said not a week goes by without seeing a patient presenting with symptoms of cannabinoid hyperemesis syndrome.
Antiemetics have very little effect in patients experiencing cyclic vomiting, but some patients will respond to dronabinol (Marinol), which is the active ingredient in marijuana that suppresses nausea and encourages eating, Dr. Persoff said.
“These patients can get profoundly dehydrated and miserable, with the misery only transiently improved by hot showers and walls of steam,” he added.
In addition, Dr. Monte said that these patients may require antiemetics, IV fluids, and, frequently, antipsychotics, such as haloperidol or sublingual olanzapine, to control their symptoms.
There have also been reports of hospital admission due to marijuana-related burns. People are at risk for these burns when attempting to make or consume oil-based cannabis concentrates.
According to Dr. Monte's analysis, the University of Colorado burn center has had 31 admissions for marijuana-related burns in the last 2 years, with some involving more than 70% of the body surface. The article says that “the majority of these were flash burns that occurred during THC extraction from marijuana plants using butane as a solvent.”
Dr. Persoff said that when he is discussing marijuana use with patients who present with these marijuana-related health issues, he makes sure not to stigmatize them or make them feel guilty for something that is now legal. However, that does not mean that clinicians should not take advantage of the opportunity to counsel patients on marijuana use.
“It is striking that many of the patients are convinced of the benefits of marijuana and are resistant to counseling to the contrary,” Dr. Persoff said. “I have never had a patient with marijuana-related cyclic vomiting syndrome acknowledge that marijuana could perhaps be the cause of the problem.”
When counseling patients who smoke the drug, Dr. Savage often brings up the fact that they are smoking an unfiltered product, about which there are few data on long-term pulmonary or other effects.
For patients who present with depression and mention marijuana use as their way of coping, Dr. Savage discusses the link between marijuana and increased risk for depression and anxiety and stresses that what patients think is helping their symptoms may, in fact, be worsening them.
In addition, counseling about edibles is also of great importance for those who might use them, Dr. Savage added.
“I generally don't document specific THC amounts for patients who present with side effects due to isolated ingestion, but I will talk about dosing, delayed side effects, and avoiding repeated dosing if they don't feel the effects of the edible,” Dr. Savage said.
Colorado's adoption of emergency rules on edible packaging is one example of how policy on marijuana is being adapted in response to the effects of recreational legalization. The edible packaging rules may not go far enough, in Dr. Savage's opinion. He thinks there should be standardization of the font size and positioning of information on these packages.
Physicians as well as patients are affected by the lack of reliable medical information about marijuana, the experts said.
According to Dr. Monte, researchers are doing marijuana studies on, for example, epilepsy and marijuana use, but they are not legally able to give the participants marijuana or THC as part of the study. Instead, patients have to use the drug on their own and then get blood drawn.
“This clearly brings up issues of bias and control of the doses and concentrations of the products being used,” Dr. Monte said. “All those things affect the quality of these studies.”
Dr. Persoff would like the federal government to deregulate marijuana as a Schedule I substance to allow more research to be conducted.
“If there are benefits from the drug, I would like it to be more widely available, but if there is more harm than good, I need to know that information, too, in order to educate my patients,” he said, adding that policy changes that make consumer education more of a priority are also of vital importance.
Developing educational materials is one of the first things that Dr. Monte would advise physicians or institutions to do in states where marijuana legalization is underway. When patients ask their physicians about marijuana use, it's helpful to have handouts to supplement the physician/patient conversation.
In addition, physicians and institutions should create policies of asking patients about marijuana use, separately from other illegal drugs, Dr. Monte advised. “As legalization happens, more patients will use marijuana because of increased availability, and physicians need to know what patients are taking, at a minimum, because of other drug/drug interactions,” he said.
Finally, physicians should take advantage of the information available on marijuana addiction and intoxication and educate themselves about the signs and symptoms of cannabinoid hyperemesis syndrome, Dr. Persoff said.
“The number of patients I see with marijuana-related issues is still relatively small overall,” he said. “I encourage physicians to be flexible and nonjudgmental, but also keep an eye out for patients who may be in need of medical attention due to these issues.”