AAP: Marijuana is harmful, addictive, and on the rise

Marijuana is dangerous, and you need to know how dangerous to adequately counsel adolescent patients and their families.

The growing number of states legalizing marijuana, whether exclusively for medical use or for recreational use, is changing the landscape for physicians, addiction specialists, and others working in public health, explained Dr. Miriam Schizer of the adolescent substance abuse program at Boston Children’s Hospital.

Currently, 23 states plus Washington have legalized medical marijuana, and 4 states plus Washington have legalized recreational use, Dr. Schizer said at the annual meeting of the American Academy of Pediatrics. Cannabis products are expanding rapidly, with many becoming more potent, but misconceptions about marijuana use also are potent and growing.

©iStock/ThinkStockPhotos.com

The proportion of high school seniors who believe marijuana carries a “great risk of harm” is nearly at an all-time low, based on findings from the Monitoring the Future survey. With annual samples of approximately 50,000 8th, 10th and 12th grade students each year, the survey provides a glimpse into long-term trends in adolescents’ attitudes and behaviors regarding substance use. Just over a third of high school seniors (36%) perceived marijuana to have a great risk of harm in 2014, one of the lowest recorded numbers since the survey began in 1975. And 14% of seniors surveyed reported having used marijuana in the past month.

Understanding the mechanisms of THC

The primary psychoactive ingredient in marijuana is delta-9 tetrahydrocannabinol, or THC, one of more than 100 cannabinoids in marijuana. This fat-soluble molecule crosses both the blood-brain barrier and the placenta and accumulates in adipose tissue, where its half-life ranges from several days to a week. Its concentration in cannabis products also has increased from an average of less than 4% in 1994 to an average of 9% in cannabis products in 2008.

The way THC makes its way into adolescents’ systems varies: Smoking buds and leaves is the most common, but people also eat edible products, inhale cannabis through hookahs or e-cigarette–like “vaping” systems, or use hash oil “dabbing” for an exceptionally potent dose.

While the positive effects of cannabis use are what keep users coming back, the negative effects are just as common and can carry over until the day after, like a hangover. Those include paranoia, anxiety, irritability, impaired short-term memory, poor attention or judgment, poor coordination, distorted spatial perception, and an altered sense of the passage of time. The positive effects that users report include reduced anxiety, increased sociability, the perception that time slows down, an increased appetite, decreased pain, and overall euphoria.

Physiologic effects – peaking 30 minutes after inhalation or 2-4 hours after ingestion – can include tachycardia up to 20-50 beats per minute above baseline, increased blood pressure, bronchial relaxation, red eyes, and dry mouth and throat. These effects increase with the concentration of THC, also increasing the likelihood of paranoia, panic, hallucinations, vomiting, erratic mood swings, and aggressive behavior.

Following the discovery of cannabinoid receptors in the brain in 1988, scientists learned that the brain contains its own cannabinoid known as anandamide, giving rise to an endocannabinoid system in the brain. This system shapes brain development, supports myelin growth on neurons, and controls neuron activity. Both THC and anandamide play a role in regulating neurotransmitters such as dopamine, glutamate, endorphins, and serotonin, but THC has much stronger, longer-lasting effects and consequently interferes with cell function and growth.

Misconceptions about marijuana use

Dr. Schizer addressed the most common myths about marijuana use, pointing out that it is harmful to human health, it is addictive, and it does impair driving. Short-term harms include impaired short-term memory and motor coordination, altered judgment, and, in higher doses, paranoia and psychosis.

“There is a link to worsening depression and anxiety over time,” Dr. Schizer said. “Something is emerging very clearly: Among individuals with a genetic disposition to psychotic disorder, there’s an increased risk of developing the psychotic disorder.”

Long-term use can alter brain development, particularly among those using it in early adolescence, and lead to higher dropout rates, a lower IQ, and a poorer sense of life satisfaction. In one study of 1,037 individuals tracked from age 13 to 38 years, the average IQ of those who never used marijuana ranged from 99.8 to 100.6, compared with 99.7 to 93.9 among those dependent on marijuana for at least 3 years (Proc Natl Acad Sci USA. 2012 Oct 2;109[40]:E2657-64).

Marijuana use also has adverse effects on the lungs, on male and female sexual function, and on the cardiovascular system. In pregnant women using marijuana, the fetus is exposed to THC through the placenta and umbilical cord, receives less oxygen, and has a higher risk of birth defects.

Approximately 9% of users develop an addiction to marijuana, but that nearly doubles to 17% among users who start in adolescence, according to the National Institute on Drug Abuse.

“The earlier they are when they start, the more likely they are to develop an addiction,” Dr. Schizer said, pointing out that 88% of all substance abuse treatment admissions among adolescents aged 12-17 years involved marijuana, according to 2012 Substance Abuse and Mental Health Services Administration data. By age 21 years, approximately 4% of users are addicted, but about a quarter to half of daily users develop an addiction. Further evidence of marijuana’s addictiveness are “bona fide withdrawal symptoms,” which typically peak about 10 days after last use, and can include restlessness, anxiety, increased irritability or aggression, difficulty falling and staying asleep, nightmares or strange dreams, decreased appetite, and weight loss.

Driving impairment under the influence of marijuana results from poorer attention, worse working memory, lack of coordination, poorer reaction time, and lack of visual perception caused by THC. In a graphic Dr. Schizer presented comparing Colorado to 34 states without medical marijuana, the proportion of drivers testing positive for marijuana in fatal crashes began sharply increasing in 2009, the year widespread medical marijuana was implemented in Colorado.

“In particular, we are thinking about relatively inexperienced drivers, so the effects are even more important,” Dr. Schizer said.

Medical marijuana

What began as an Institute of Medicine recommendation for “compassionate use” to relieve suffering in terminally ill patients has become a movement to medicalize marijuana despite limited evidence of its therapeutic benefits, Dr. Schizer explained. Since California legalized medical marijuana in 1996, many other states have followed suit. Yet the only condition for which modest evidence supports its use is treating adults’ nausea and vomiting resulting from chemotherapy. For chronic pain, anorexia associated with HIV/AIDS, and neurologic problems such as multiple sclerosis, the evidence is not sufficient to show therapeutic efficacy, and no studies have looked at medical marijuana use in children.

“Marijuana is not a medication,” Dr. Schizer said. “There is therapeutic potential in these cannabinoids, but that’s not the same as directing patients to using medical marijuana. We know that penicillin was originally derived from mold, but you would give patients penicillin, not a slice of moldy bread” to treat a bacterial infection.

Actual medical cannabinoids approved for treatments include Marinol and Sativex. The Food and Drug Administration has approved Marinol, a slow-acting oral formulation, to treat weight loss in patients with anorexia or AIDS and to treat nausea and vomiting from chemotherapy. Ongoing phase III clinical studies are testing Sativex for the treatment of advanced cancer pain. To suggest that a patient use commercially available marijuana therapeutically would be akin to sending patients to an opium den instead of prescribing a precise opioid for pain, Dr. Schizer suggested. “I think it’s unconscionable for doctors to prescribe something that is smoked.”

Data from Colorado and Oregon suggest few individuals with medical marijuana cards may be using it for serious illnesses, Dr. Schizer pointed out. Less than 2% of medical marijuana cardholders report cancer, HIV/AIDS, glaucoma,i or multiple sclerosis as their reasons for using marijuana. The typical profile of a cardholder is a 32-year-old white man with a history of alcohol and cocaine abuse and no history of life-threatening illnesses, she said. According to the Colorado Department of Public Health and Environment, 12% of medical marijuana users report using it for severe nausea, 17% for muscle spasms, and 94% for “severe pain.”

Meanwhile, Colorado’s legalization of recreational marijuana imparts several lessons, Dr. Schizer said. The highest rate of teen marijuana use in the United States occurs in Denver, and 11% of teens report using marijuana in the past month, compared with a national average of 8%. Drug-related school suspensions have increased, and the rate of car crashes in which the driver tested positive for marijuana tripled between January 2014, when stores opened, and April 2014.

Dr. Schizer reported no relevant financial disclosures.

Marijuana is dangerous, and you need to know how dangerous to adequately counsel adolescent patients and their families.

The growing number of states legalizing marijuana, whether exclusively for medical use or for recreational use, is changing the landscape for physicians, addiction specialists, and others working in public health, explained Dr. Miriam Schizer of the adolescent substance abuse program at Boston Children’s Hospital.

Currently, 23 states plus Washington have legalized medical marijuana, and 4 states plus Washington have legalized recreational use, Dr. Schizer said at the annual meeting of the American Academy of Pediatrics. Cannabis products are expanding rapidly, with many becoming more potent, but misconceptions about marijuana use also are potent and growing.

©iStock/ThinkStockPhotos.com

The proportion of high school seniors who believe marijuana carries a “great risk of harm” is nearly at an all-time low, based on findings from the Monitoring the Future survey. With annual samples of approximately 50,000 8th, 10th and 12th grade students each year, the survey provides a glimpse into long-term trends in adolescents’ attitudes and behaviors regarding substance use. Just over a third of high school seniors (36%) perceived marijuana to have a great risk of harm in 2014, one of the lowest recorded numbers since the survey began in 1975. And 14% of seniors surveyed reported having used marijuana in the past month.

Understanding the mechanisms of THC

The primary psychoactive ingredient in marijuana is delta-9 tetrahydrocannabinol, or THC, one of more than 100 cannabinoids in marijuana. This fat-soluble molecule crosses both the blood-brain barrier and the placenta and accumulates in adipose tissue, where its half-life ranges from several days to a week. Its concentration in cannabis products also has increased from an average of less than 4% in 1994 to an average of 9% in cannabis products in 2008.

The way THC makes its way into adolescents’ systems varies: Smoking buds and leaves is the most common, but people also eat edible products, inhale cannabis through hookahs or e-cigarette–like “vaping” systems, or use hash oil “dabbing” for an exceptionally potent dose.

While the positive effects of cannabis use are what keep users coming back, the negative effects are just as common and can carry over until the day after, like a hangover. Those include paranoia, anxiety, irritability, impaired short-term memory, poor attention or judgment, poor coordination, distorted spatial perception, and an altered sense of the passage of time. The positive effects that users report include reduced anxiety, increased sociability, the perception that time slows down, an increased appetite, decreased pain, and overall euphoria.

Physiologic effects – peaking 30 minutes after inhalation or 2-4 hours after ingestion – can include tachycardia up to 20-50 beats per minute above baseline, increased blood pressure, bronchial relaxation, red eyes, and dry mouth and throat. These effects increase with the concentration of THC, also increasing the likelihood of paranoia, panic, hallucinations, vomiting, erratic mood swings, and aggressive behavior.

Following the discovery of cannabinoid receptors in the brain in 1988, scientists learned that the brain contains its own cannabinoid known as anandamide, giving rise to an endocannabinoid system in the brain. This system shapes brain development, supports myelin growth on neurons, and controls neuron activity. Both THC and anandamide play a role in regulating neurotransmitters such as dopamine, glutamate, endorphins, and serotonin, but THC has much stronger, longer-lasting effects and consequently interferes with cell function and growth.

Misconceptions about marijuana use

Dr. Schizer addressed the most common myths about marijuana use, pointing out that it is harmful to human health, it is addictive, and it does impair driving. Short-term harms include impaired short-term memory and motor coordination, altered judgment, and, in higher doses, paranoia and psychosis.

“There is a link to worsening depression and anxiety over time,” Dr. Schizer said. “Something is emerging very clearly: Among individuals with a genetic disposition to psychotic disorder, there’s an increased risk of developing the psychotic disorder.”

Long-term use can alter brain development, particularly among those using it in early adolescence, and lead to higher dropout rates, a lower IQ, and a poorer sense of life satisfaction. In one study of 1,037 individuals tracked from age 13 to 38 years, the average IQ of those who never used marijuana ranged from 99.8 to 100.6, compared with 99.7 to 93.9 among those dependent on marijuana for at least 3 years (Proc Natl Acad Sci USA. 2012 Oct 2;109[40]:E2657-64).

Marijuana use also has adverse effects on the lungs, on male and female sexual function, and on the cardiovascular system. In pregnant women using marijuana, the fetus is exposed to THC through the placenta and umbilical cord, receives less oxygen, and has a higher risk of birth defects.

Approximately 9% of users develop an addiction to marijuana, but that nearly doubles to 17% among users who start in adolescence, according to the National Institute on Drug Abuse.

“The earlier they are when they start, the more likely they are to develop an addiction,” Dr. Schizer said, pointing out that 88% of all substance abuse treatment admissions among adolescents aged 12-17 years involved marijuana, according to 2012 Substance Abuse and Mental Health Services Administration data. By age 21 years, approximately 4% of users are addicted, but about a quarter to half of daily users develop an addiction. Further evidence of marijuana’s addictiveness are “bona fide withdrawal symptoms,” which typically peak about 10 days after last use, and can include restlessness, anxiety, increased irritability or aggression, difficulty falling and staying asleep, nightmares or strange dreams, decreased appetite, and weight loss.

Driving impairment under the influence of marijuana results from poorer attention, worse working memory, lack of coordination, poorer reaction time, and lack of visual perception caused by THC. In a graphic Dr. Schizer presented comparing Colorado to 34 states without medical marijuana, the proportion of drivers testing positive for marijuana in fatal crashes began sharply increasing in 2009, the year widespread medical marijuana was implemented in Colorado.

“In particular, we are thinking about relatively inexperienced drivers, so the effects are even more important,” Dr. Schizer said.

Medical marijuana

What began as an Institute of Medicine recommendation for “compassionate use” to relieve suffering in terminally ill patients has become a movement to medicalize marijuana despite limited evidence of its therapeutic benefits, Dr. Schizer explained. Since California legalized medical marijuana in 1996, many other states have followed suit. Yet the only condition for which modest evidence supports its use is treating adults’ nausea and vomiting resulting from chemotherapy. For chronic pain, anorexia associated with HIV/AIDS, and neurologic problems such as multiple sclerosis, the evidence is not sufficient to show therapeutic efficacy, and no studies have looked at medical marijuana use in children.

“Marijuana is not a medication,” Dr. Schizer said. “There is therapeutic potential in these cannabinoids, but that’s not the same as directing patients to using medical marijuana. We know that penicillin was originally derived from mold, but you would give patients penicillin, not a slice of moldy bread” to treat a bacterial infection.

Actual medical cannabinoids approved for treatments include Marinol and Sativex. The Food and Drug Administration has approved Marinol, a slow-acting oral formulation, to treat weight loss in patients with anorexia or AIDS and to treat nausea and vomiting from chemotherapy. Ongoing phase III clinical studies are testing Sativex for the treatment of advanced cancer pain. To suggest that a patient use commercially available marijuana therapeutically would be akin to sending patients to an opium den instead of prescribing a precise opioid for pain, Dr. Schizer suggested. “I think it’s unconscionable for doctors to prescribe something that is smoked.”

Data from Colorado and Oregon suggest few individuals with medical marijuana cards may be using it for serious illnesses, Dr. Schizer pointed out. Less than 2% of medical marijuana cardholders report cancer, HIV/AIDS, glaucoma,i or multiple sclerosis as their reasons for using marijuana. The typical profile of a cardholder is a 32-year-old white man with a history of alcohol and cocaine abuse and no history of life-threatening illnesses, she said. According to the Colorado Department of Public Health and Environment, 12% of medical marijuana users report using it for severe nausea, 17% for muscle spasms, and 94% for “severe pain.”

Meanwhile, Colorado’s legalization of recreational marijuana imparts several lessons, Dr. Schizer said. The highest rate of teen marijuana use in the United States occurs in Denver, and 11% of teens report using marijuana in the past month, compared with a national average of 8%. Drug-related school suspensions have increased, and the rate of car crashes in which the driver tested positive for marijuana tripled between January 2014, when stores opened, and April 2014.

Dr. Schizer reported no relevant financial disclosures.

Marijuana is dangerous, and you need to know how dangerous to adequately counsel adolescent patients and their families.

The growing number of states legalizing marijuana, whether exclusively for medical use or for recreational use, is changing the landscape for physicians, addiction specialists, and others working in public health, explained Dr. Miriam Schizer of the adolescent substance abuse program at Boston Children’s Hospital.

Currently, 23 states plus Washington have legalized medical marijuana, and 4 states plus Washington have legalized recreational use, Dr. Schizer said at the annual meeting of the American Academy of Pediatrics. Cannabis products are expanding rapidly, with many becoming more potent, but misconceptions about marijuana use also are potent and growing.

©iStock/ThinkStockPhotos.com

The proportion of high school seniors who believe marijuana carries a “great risk of harm” is nearly at an all-time low, based on findings from the Monitoring the Future survey. With annual samples of approximately 50,000 8th, 10th and 12th grade students each year, the survey provides a glimpse into long-term trends in adolescents’ attitudes and behaviors regarding substance use. Just over a third of high school seniors (36%) perceived marijuana to have a great risk of harm in 2014, one of the lowest recorded numbers since the survey began in 1975. And 14% of seniors surveyed reported having used marijuana in the past month.

Understanding the mechanisms of THC

The primary psychoactive ingredient in marijuana is delta-9 tetrahydrocannabinol, or THC, one of more than 100 cannabinoids in marijuana. This fat-soluble molecule crosses both the blood-brain barrier and the placenta and accumulates in adipose tissue, where its half-life ranges from several days to a week. Its concentration in cannabis products also has increased from an average of less than 4% in 1994 to an average of 9% in cannabis products in 2008.

The way THC makes its way into adolescents’ systems varies: Smoking buds and leaves is the most common, but people also eat edible products, inhale cannabis through hookahs or e-cigarette–like “vaping” systems, or use hash oil “dabbing” for an exceptionally potent dose.

While the positive effects of cannabis use are what keep users coming back, the negative effects are just as common and can carry over until the day after, like a hangover. Those include paranoia, anxiety, irritability, impaired short-term memory, poor attention or judgment, poor coordination, distorted spatial perception, and an altered sense of the passage of time. The positive effects that users report include reduced anxiety, increased sociability, the perception that time slows down, an increased appetite, decreased pain, and overall euphoria.

Physiologic effects – peaking 30 minutes after inhalation or 2-4 hours after ingestion – can include tachycardia up to 20-50 beats per minute above baseline, increased blood pressure, bronchial relaxation, red eyes, and dry mouth and throat. These effects increase with the concentration of THC, also increasing the likelihood of paranoia, panic, hallucinations, vomiting, erratic mood swings, and aggressive behavior.

Following the discovery of cannabinoid receptors in the brain in 1988, scientists learned that the brain contains its own cannabinoid known as anandamide, giving rise to an endocannabinoid system in the brain. This system shapes brain development, supports myelin growth on neurons, and controls neuron activity. Both THC and anandamide play a role in regulating neurotransmitters such as dopamine, glutamate, endorphins, and serotonin, but THC has much stronger, longer-lasting effects and consequently interferes with cell function and growth.

Misconceptions about marijuana use

Dr. Schizer addressed the most common myths about marijuana use, pointing out that it is harmful to human health, it is addictive, and it does impair driving. Short-term harms include impaired short-term memory and motor coordination, altered judgment, and, in higher doses, paranoia and psychosis.

“There is a link to worsening depression and anxiety over time,” Dr. Schizer said. “Something is emerging very clearly: Among individuals with a genetic disposition to psychotic disorder, there’s an increased risk of developing the psychotic disorder.”

Long-term use can alter brain development, particularly among those using it in early adolescence, and lead to higher dropout rates, a lower IQ, and a poorer sense of life satisfaction. In one study of 1,037 individuals tracked from age 13 to 38 years, the average IQ of those who never used marijuana ranged from 99.8 to 100.6, compared with 99.7 to 93.9 among those dependent on marijuana for at least 3 years (Proc Natl Acad Sci USA. 2012 Oct 2;109[40]:E2657-64).

Marijuana use also has adverse effects on the lungs, on male and female sexual function, and on the cardiovascular system. In pregnant women using marijuana, the fetus is exposed to THC through the placenta and umbilical cord, receives less oxygen, and has a higher risk of birth defects.

Approximately 9% of users develop an addiction to marijuana, but that nearly doubles to 17% among users who start in adolescence, according to the National Institute on Drug Abuse.

“The earlier they are when they start, the more likely they are to develop an addiction,” Dr. Schizer said, pointing out that 88% of all substance abuse treatment admissions among adolescents aged 12-17 years involved marijuana, according to 2012 Substance Abuse and Mental Health Services Administration data. By age 21 years, approximately 4% of users are addicted, but about a quarter to half of daily users develop an addiction. Further evidence of marijuana’s addictiveness are “bona fide withdrawal symptoms,” which typically peak about 10 days after last use, and can include restlessness, anxiety, increased irritability or aggression, difficulty falling and staying asleep, nightmares or strange dreams, decreased appetite, and weight loss.

Driving impairment under the influence of marijuana results from poorer attention, worse working memory, lack of coordination, poorer reaction time, and lack of visual perception caused by THC. In a graphic Dr. Schizer presented comparing Colorado to 34 states without medical marijuana, the proportion of drivers testing positive for marijuana in fatal crashes began sharply increasing in 2009, the year widespread medical marijuana was implemented in Colorado.

“In particular, we are thinking about relatively inexperienced drivers, so the effects are even more important,” Dr. Schizer said.

Medical marijuana

What began as an Institute of Medicine recommendation for “compassionate use” to relieve suffering in terminally ill patients has become a movement to medicalize marijuana despite limited evidence of its therapeutic benefits, Dr. Schizer explained. Since California legalized medical marijuana in 1996, many other states have followed suit. Yet the only condition for which modest evidence supports its use is treating adults’ nausea and vomiting resulting from chemotherapy. For chronic pain, anorexia associated with HIV/AIDS, and neurologic problems such as multiple sclerosis, the evidence is not sufficient to show therapeutic efficacy, and no studies have looked at medical marijuana use in children.

“Marijuana is not a medication,” Dr. Schizer said. “There is therapeutic potential in these cannabinoids, but that’s not the same as directing patients to using medical marijuana. We know that penicillin was originally derived from mold, but you would give patients penicillin, not a slice of moldy bread” to treat a bacterial infection.

Actual medical cannabinoids approved for treatments include Marinol and Sativex. The Food and Drug Administration has approved Marinol, a slow-acting oral formulation, to treat weight loss in patients with anorexia or AIDS and to treat nausea and vomiting from chemotherapy. Ongoing phase III clinical studies are testing Sativex for the treatment of advanced cancer pain. To suggest that a patient use commercially available marijuana therapeutically would be akin to sending patients to an opium den instead of prescribing a precise opioid for pain, Dr. Schizer suggested. “I think it’s unconscionable for doctors to prescribe something that is smoked.”

Data from Colorado and Oregon suggest few individuals with medical marijuana cards may be using it for serious illnesses, Dr. Schizer pointed out. Less than 2% of medical marijuana cardholders report cancer, HIV/AIDS, glaucoma,i or multiple sclerosis as their reasons for using marijuana. The typical profile of a cardholder is a 32-year-old white man with a history of alcohol and cocaine abuse and no history of life-threatening illnesses, she said. According to the Colorado Department of Public Health and Environment, 12% of medical marijuana users report using it for severe nausea, 17% for muscle spasms, and 94% for “severe pain.”

Meanwhile, Colorado’s legalization of recreational marijuana imparts several lessons, Dr. Schizer said. The highest rate of teen marijuana use in the United States occurs in Denver, and 11% of teens report using marijuana in the past month, compared with a national average of 8%. Drug-related school suspensions have increased, and the rate of car crashes in which the driver tested positive for marijuana tripled between January 2014, when stores opened, and April 2014.

Dr. Schizer reported no relevant financial disclosures.