Twenty-seven papers and 68 patients works out to about two and a half patients per report [1], which tells you what kind of evidence this is: clinicians writing up the person in front of them, and this review is the first to pull those write-ups into one set [21]. Stack case reports and you get a case series, and a case series is a numerator. No one counted the spoonfuls eaten, so this review cannot say what share of people who try mad honey end up on a drip, or whether that share is moving as sales go online.
The dates carry the same caution. The search window opened in 1976, but the earliest case it turned up is from 2009 [2], leaving 33 years of the window empty [5], which is more plausibly a change in publishing habit than a toxin that appeared in 2009. Across the 18 calendar years that do contain cases, the published record runs to fewer than four patients a year [2].
The dose figures are where the piece is usefully honest. One passage puts a teaspoonful at pleasantly warm and slightly lightheaded, and more than a few tablespoons at a life-threateningly slow heart rate [11]; a later passage puts the onset of interference with cardiac electrical signalling at more than about a teaspoon [12]. Read "a few" as three and the two thresholds sit roughly ninefold apart [4]. Since potency varies by batch, season and location [10], I take the inconsistency as the state of the evidence rather than carelessness: the same spoon is a different dose depending on which cliff and which spring filled it. The Gurung answer to that variance is to know the source [13], and provenance is exactly what a parcel drops [14].
The demand side is not recreational. About 49 of the 68 patients were middle-aged men [3], and the pharmacology they are relying on has some support: in rat models, small amounts do lower blood pressure [18]. The author's stated problem is the distance between a medicinal dose and a harmful one [19]. A man titrating his own blood pressure from an unassayed jar is guessing at where the low side of that distance actually is.
The reassuring end of the file has conditions attached. Nepal has reported no deaths from this honey [8], and patients there are treated with intravenous fluids and atropine, with most recovering in a day or two [9]. Symptoms arrive within 30 to 60 minutes [7], so the exposure is usually recent when the patient reaches care; the case that prompted the review was a man who reached hospital about half an hour after eating honey brought back from the hills, with his heart rate down and his blood pressure collapsed [20]. In a department that has never taken a honey history, the same presentation is unexplained bradycardia in a middle-aged man.
One loose thread worth following: the grayanotoxin is a plant's deterrent aimed at insects that rob nectar without pollinating [16], and the bee that concentrates it appears unbothered, with the mechanism still unexplained, even though tolerance in insects feeding on toxic plants rarely comes free [17].
