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or all of the hallucinogenic drug experiences after a period of normal

consciousness in a person who used the drug previously. The flashbacks may last

from minutes to days or months (usually a few hours). The estimated prevalence of

flashbacks varies widely in studies, and the etiology is still unclear.

65 Flashbacks can

occur spontaneously or be triggered by exercise, stress, or another drug (e.g.,

marijuana).

64 Treatment remains anecdotal; no randomized, controlled trials have

evaluated the efficacy of pharmacotherapy for HPPD.

LSD and other classic hallucinogens have low potential for chronic use disorder.

There does not appear to be a clinically important withdrawal syndrome associated

with their use. The rapid development of tolerance that occurs with these drugs may

explain the intermittent use patterns commonly seen.

MDMA

CASE 90-8

QUESTION 1: R.X. and her friend P.B. go to “raves” (all-night dance parties) every weekend and usually

take ecstasy (MDMA). R.X. says it makes her feel like “I love everyone around me,” and P.B. likes to be able

to “dance all night without getting tired.” Are these effects common with MDMA?

Merck Pharmaceuticals patented MDMA in 1914, but it was not until the 1950s

that its use was examined in animal studies, when the US Army Intelligence

investigated it as a “brainwashing” agent. By the late 1970s, a few therapists and

psychiatrists began using the drug with reported success in patients with a wide range

of conditions.

66 MDMA produces a very manageable and comfortable entactogenic

effect, during which the person has a clear sensorium. The experience can be

recalled in detail, and the insights gained during the session can be incorporated into

normal life. The public gave several names to this drug, such as ecstasy, XTC, Adam,

and M&Ms. The media became aware of the anecdotal reports from both

psychiatrists and people self-experimenting with MDMA. In 1985, the DEA made

MDMA a schedule I drug. Subsequently, supplies of the drug proliferated in the

public illicit marketplace, and its popularity soared. In 2001, after successful

lobbying by researchers interested in reinstituting MDMA in clinical practice, the

FDA granted approval for a pilot study investigating the therapeutic use of MDMA in

the treatment of posttraumatic stress disorder (PTSD). Results of this placebocontrolled study indicate that MDMA is very effective (83% vs. 25%) in treating

PTSD.

67 The effects of MDMA are mainly exerted by three neurochemical

mechanisms: blockade of serotonin reuptake, stimulation of serotonin release, and

stimulation of dopamine release.

68 The common psychological effects of MDMA

intoxication include an overall heightened sense of empathy, interpersonal closeness,

increased acceptance of others, and a powerful sense of well-being.

69 The experience

is influenced by set and setting. The amphetamine-like side effects include mydriasis,

tachycardia, sweating, increased energy and alertness, bruxism, nausea, and

anorexia.

70 Users generally ingest MDMA in tablet form, and the onset of action is

usually after 30 to 60 minutes. Some users take a “booster” dose after 2 hours. The

usual duration of action of MDMA is 4 to 6 hours, and the half-life is approximately

8 hours. MDMA users in the rave scene often “stack” multiple doses, and polydrug

use is common. The combined use of ecstasy and LSD is referred to as “candy

flipping.”

68

R.X.’s feelings of love for everyone are consistent with the empathogenic effects

of MDMA, whereas P.B. is enjoying the amphetamine-like effects of increased

energy to dance all night.

ADVERSE EFFECTS

CASE 90-8, QUESTION 2: Several hours after taking MDMA, P.B. is still dancing. She begins to feel hot

and realizes she is profusely sweating. On her way to the bar for a drink, she begins to feel confused and

collapses to the floor. Her friends witness her having a seizure and call 9-1-1. What is happening to P.B.?

The rave scene, with its crowded conditions and often-high ambient temperatures,

has contributed to many adverse effects associated with MDMA ingestion. Because

of their increased physical activity, the ravers may become dehydrated. Additionally,

supplies of MDMA have been notoriously unreliable. Many other drugs have been

misrepresented as MDMA, including other phenethylamines such as 3,4-

methylenedioxy-amphetamine (MDA) and paramethoxyamphetamine (PMA);

amphetamine; cocaine; opiates; ketamine; and dextromethorphan. The common

polydrug use practiced at raves compounds the problem. Dextromethorphan taken at

high doses for its dissociative properties competes with MDMA for hepatic

metabolism, and its anticholinergic effects block perspiration, potentially leading to

overheating.

66

The most dangerous adverse physical effect of MDMA is hyperthermia. MDMA

has a slight affinity for the 5-HT2

receptor, and the increased body temperature may

be the result of this activation.

68 The hyperthermia has led to rhabdomyolysis, and

acute renal and hepatic failure, disseminated intravascular coagulation (DIC), and

death.

71 DIC has been the most common cause of death. Treatment of hyperthermia

involves cooling measures and IV fluids. Benzodiazepines (e.g., lorazepam 2 mg IM

or IV) and dantrolene (1 mg/kg IV) may be helpful. Other adverse physical effects

can include hypertension, cardiac arrhythmias, convulsions, cerebrovascular

accident, hepatitis, and hyponatremia (from over ingestion of water as a harm

reduction measure to avoid hyperthermia).

70,71

In 2011, there were 22,498, emergency

department visits associated with MDMA use.

72 Adverse psychological effects are

also possible, including anxiety, depression, panic attacks, agitation, paranoia, and

rarely psychosis. The treatment of these psychological adverse effects is the same as

for those associated with the classic hallucinogens, including talk-down therapy and

benzodiazepine administration. P.B. may be suffering from MDMA-induced

hyperthermia and needs urgent medical evaluation.

LONG-TERM EFFECTS

CASE 90-8, QUESTION 3: R.X. has read in the newspaper that MDMA is associated with “brain damage”

and is worried that she has caused permanent damage to her brain. What are the long-term effects of MDMA?

Animal studies have consistently demonstrated long-term MDMA-induced

serotonin depletion. This has been evidenced by lower levels of serotonin, decreased

metabolite levels, lowered levels of tryptophan hydroxylase, and loss of serotonin

reuptake transporters.

66 This may explain the induction of panic attacks for chronic

users. MDMA damages serotonin axonal projections; axonal resprouting and

regeneration do occur, but it is unclear whether these new projections are

damaged.

66,73 Both hepatotoxicity and neuronal toxicity occur with MDMA use and is

suspected to be due to oxidative stress, mitochondrial dysfunction, and

excitotoxicity.

60

Several retrospective studies in humans have claimed lowered cognitive

performance in MDMA users compared with nonusers. These studies have

confounding variables, such as other drug use and adulterant exposure and lifestyle

factors.

66,73

p. 1887

p. 1888

Use of MDMA does not appear to produce physical dependence, but some users

may become psychologically dependent. Tolerance to the empathogenic effects

develops rapidly and may last 24 to 36 hours. This may explain in part the more

common practice of sporadic dosing of the drug.

57,69 No distinctive withdrawal

syndrome has been described that would require pharmacologic treatment.

MARIJUANA

Marijuana is the most widely used illicit substance in the United States. In 2014, 35.1

million Americans reported using marijuana in the past year.

4 The main psychoactive

ingredient in the Cannabis sativa plant is Δ-9-tetrahydrocannabinol (THC), although

the plant is known to contain more than 70 cannabinoids.

74

In the United States, the

dried, chopped leaves and flowers of the Cannabis plant (grass, pot, weed, green

bud, chronic, mary jane) are rolled into a cigarette paper (marijuana cigarette, known

as a joint or blunt; a “roach” is the butt of the marijuana cigarette) or smoked in a

pipe or water pipe (“bong”). Each joint usually weighs 0.5 to 1 g, for a THC content

of about 5 mg (very weak), 30 mg (average), or 150 mg (highest-quality sinsemilla).

The sinsemilla (Spanish for “without seeds”) growing technique involves separating

the female plants from the males before pollination occurs. This results in female

plants with higher amounts of THC, up to 14%.

75

The raw resin of the Cannabis plant can be pressed into cakes, balls, or sticks,

called hashish (“hash,” “temple balls”), which is smoked or eaten. Hashish can

contain up to 8% THC. The oils can be extracted from the plant with organic solvents

to produce “hash oil,” perhaps the most potent Cannabis derivative, with THC

concentrations of up to 50%.

75

Researchers in cannabinoid neurobiology have discovered two cannabinoid

receptors in the CNS: CB1 and CB2

; however, additional receptors have been

proposed. Research has demonstrated that the main pharmacologic and addictive

effects are almost completely mediated by the CB1

receptor.

75

In addition, five

endogenous cannabinoids (endocannabinoids) that act at the cannabinoid receptors

have been discovered.

76 The best known are arachidonic acid ethanolamide

(anandamide) and 2-arachidonoylglycerol (2-AG).

76 Considerable evidence exists

supporting the role of THC–opioid interactions with enhanced antinociception.

Cannabinoids have been shown to release endogenous opioids, and cannabinoid

receptors colocalize with substance P (the neurotransmitter responsible for

transmitting pain information) receptors in the striatum. Subsequently, investigation

of THC as an adjunct to opioid treatment of pain, prevention of opioid tolerance, and

dependence is underway.

75

Marijuana’s therapeutic potential has been the center of much public controversy.

Research on the effects of cannabinoids has led to several potential therapeutic uses,

including relief of nausea and vomiting, appetite stimulation, and treatment of pain,

epilepsy, glaucoma, and movement disorders (Parkinson disease, Huntington disease,

Tourette syndrome, multiple sclerosis).

75,77

In 1999, the State of California passed the

law SB847, which commissioned the University of California to establish the Center

for Medicinal Cannabis Research (CMCR) to expand scientific knowledge on

purported therapeutic usages of marijuana. The center’s 2010 report to the California

legislature and governor presented clinical trial findings demonstrating that cannabis

has analgesic effects in pain conditions secondary to injury or disease and that

cannabis reduces MS spasticity.

78 A synthetic form of THC, dronabinol, is available

as prescription tablets, and a synthetic cannabinoid, nabilone (Cesamet), is available

as capsules, but advocates of medicinal marijuana use argue that inhalation allows

for faster onset and easier titration of the dose. In addition, nauseated patients want to

avoid the oral route of administration. Future research focuses on developing a safer

delivery system that will be reliable, rapid, and safe. An oromucosal spray, Sativex,

derived from botanical material, is under investigation in the United States. The

principal active components are THC and cannabidiol. This cannabis extract spray

has been approved in Canada, and is also being used in the United Kingdom. A

capsule formulation containing a mixed ratio of THC and cannabidiol produced by

Cannador in Germany is also available.

75 Other alternative delivery methods may

include vaporization, patches, and suppositories.

Effects

CASE 90-9

QUESTION 1: P.H. is a 16-year-old male who is offered a marijuana cigarette (joint) by one of his friends.

He smokes it and begins to feel light-headed and euphoric. He begins laughing at everything around him. Thirty

minutes later he and his friend become very hungry (“the munchies”) and eat several candy bars. Which of

P.H.’s symptoms are consistent with marijuana use?

The pharmacologic effects sought by most users of cannabis products are sedation,

mental relaxation, euphoria, and mild hallucinogenic effects, and these effects depend

on set and setting. Other common effects that are usually perceived as pleasurable

include silliness, subjective slowing of time, gregariousness, hunger, and mild

perceptual changes of all the senses that engender an absorbing fascination with

music, eating, and other sensual and sensory activities. The state of mind generated is

referred to as “stoned,” “high,” “loaded,” “wasted,” and many other colloquial

terms. Smoking marijuana typically causes numbness and tingling of the extremities,

light-headedness, loss of concentration, and a floating sensation in the first 3 or 4

minutes. Some of these effects are probably caused by the hyperventilation

associated with deep inhalation of the smoke (referred to as a “hit” or “toke”) and

breath holding to allow maximal absorption from the lungs. During the first 10 to 30

minutes, the user may experience tachycardia (possibly palpitations), mild

diaphoresis, conjunctival injection (“red eye”), drying of the mouth, weakness,

postural hypotension, periods of tremulousness, incoordination, and ataxia along with

euphoria and the mental effects described above. These effects usually resolve by 1

to 3 hours and are followed by a 30- to 60-minute period of sleepiness before

complete clearing and return to normal consciousness. Oral ingestion of cannabis

products may delay the onset of effects by 45 to 60 minutes and prolong the

duration.

75 P.H. is experiencing euphoria, giddiness, and increased appetite,

consistent with marijuana intoxication.

Adverse Effects

CASE 90-9, QUESTION 2: P.H. smokes more marijuana with his friend. He liked it so much the first time,

he decides to take several “hits” this time. He begins to think his friend is laughing at him and notices his heart

is beating rapidly. He starts to panic. Is P.H.’s reaction caused by the marijuana?

Consistent with its widespread use, marijuana was the second most frequently

mentioned illicit substance in emergency department episodes in the United States in

2007. A total of 308,547 marijuana-related emergency department (ED) visits were

reported in 2007.

58 These visits include marijuana in combination with other drugs.

As the percentage of THC has increased in marijuana, so have the ED visits. The

majority of ED visits are from unexpected reactions, such as anxiety, paranoia, and

panic

p. 1888

p. 1889

attacks. Despite these numbers, there are no documented cases of fatality in

humans from marijuana overdose, and adverse effects tend to be self-limiting and

often do not require medical treatment.

A syndrome consisting of anxiety, paranoia, depersonalization, disorientation, and

confusion that can lead to panic states and incapacitating fear is perhaps the most

frequently reported adverse effect of marijuana. Comforting reassurance (talk-down)

and reducing stressful stimuli can alleviate this condition. The dysphoria and anxiety

usually resolve in a few hours or less with such an approach. More severe incidents

that evolve into panic reactions that are not resolved by sympathetic counseling may

be relieved with oral benzodiazepine therapy in a dose equivalent to 5 to 10 mg of

diazepam.

57 These adverse psychological reactions to cannabis products commonly

occur with inexperienced users, high doses, concomitant use of other psychoactive

drugs, and overtly stressful situations. Severe reactions requiring pharmacologic

therapy are rare. A review of the literature found that cannabis use increases the risk

of developing psychotic disorders among vulnerable or predisposed individuals and

negatively affects the course of preexisting chronic psychosis.

79

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