ACMT Toxicology Visual Pearls: The Kitchen Cabinet High

2. Myristicin

Background

Nutmeg, a common household spice, is made from the seed of the nutmeg tree, Myristica fragrans. Valued in many cultures as a treatment for numerous medical ailments [1,3], nutmeg is also used as a recreational psychotropic substance [2,3]. It is attractive to teens and young adults seeking a novel psychotropic experience because it is cheap and legal [3]. While accidental overdoses do occur, toxic ingestions are likely underreported, as nutmeg’s adverse effects are usually mild and self-resolving [3].

“You did what now?”

• Nutmeg consumption has been reported by swallowing spoonfuls of nutmeg grounds, mixing nutmeg into other foods, or encapsulation of grounds in gel capsules [2,4].
• Toxicity has resulted from accidental over-ingestion [2], intentional use for psychotropic purposes [3,4,7,8], and social media “challenges” for entertainment [9].
• Effects are dose-dependent, with toxicity reported from 5g of nutmeg [2]; 10 g of ground nutmeg is usually required to produce neuropsychological symptoms, and 25 g or more often resulting in more severe symptoms [4-8].

The Magic is in the “Myrist-ery”

• Nutmeg contains myristicin, which is thought to produce an amphetamine-derived metabolite, MMDA (3-methoxy-4,5-methylendioxy amphetamine), that shares structural characteristics with MDMA and amphetamine [2,4,5].
• Other compounds in nutmeg include trimyristin, safrole, eugenol, and elemicin; these work synergistically with myristicin to produce serotonergic, mixed GABA receptor effects, and mild monoamine oxidase inhibitory effects [2-4,6].
• Nutmeg can inhibit the activity of CYP1A2, 2E1, and 2C19, and may alter the duration of action of drugs metabolized by those CYP enzymes [6].

What are the clinical effects of nutmeg ingestion?

• Patients can experience desired effects such as a dream-like state, sedation, anxiolysis, euphoria, or hallucinations [3,4].
• Many nutmeg users experience fear, intense anxiety, an unpleasant trance-like state of which they are aware, or a sense of impending disaster [4,5,7,10].
• Symptoms such as dry mouth, tachycardia, and hallucinations may resemble antimuscarinic toxidrome [2,3,5-9].
• Headaches (aka “nutmeg hangover”) [2,7].
• Miosis or mydriasis [10].
• Seizures are reported following massive ingestion or when ingested with other substances [2,3,6,8,10].
• Serotonin syndrome is reported with concomitant administration of SSRIs or MAO inhibitors [11].

How do I manage this?

• Care for nutmeg toxicity is supportive [3].
• The onset of symptoms occurs within 1-8 hours [10].
• Effects typically resolve spontaneously within 1-2 days [10].
• Benzodiazepines can be used for agitation, seizures, and anxiety [9,10].
• Those with significant tachycardia or co-ingestion may require telemetry monitoring.
• Inform patient and parent (if applicable) education regarding nutmeg intoxication including any potential interference with current medication regimen.
• Observation of asymptomatic patients for at least 8 hours following significant ingestion has been recommended [10].

Bedside Pearls

• Nutmeg ingestion can result in a spectrum of mental status effects from sedation to delirium to hallucinations or a dream-like state.
• Onset is typically within hours and may persist for 1-2 days.
• Treatment is supportive.
• Benzodiazepines can be used for agitation and anxiety.