The Poison Review

Cardiac effects of “mad honey”: a case series. Okuyan E et al.  Clin Toxicol 2010 Jun 24 [Epub ahead of print]

Abstract

As we have noted before in a post entitled “Mad Honey Sex“, pollen of certain Rhododendron species contain grayanotoxins, agents that bind to sodium channels on cell membranes and maintain them in an open state.  In addition, they stimulate the vagus nerve causing bradycardia.  Presenting signs and symptoms of “mad honey” toxicity include nausea, vomiting, dizziness, syncope, and diaphoresis.

This case series, from Turkey, prospectively enrolled 44 consecutive patients admitted to hospital with a diagnosis of “mad honey” intoxication.  Mean systolic blood pressure was 73 mm Hg, mean diastolic pressure 52 mmHg, and mean heart rate 38 bpm.  Symptom onset occurred between 10 min and 4 h after ingestion. Dysrhythmias on initial EKG included sinus bradycardia (18 patients), complete AV block (15), and nodal rhythm (9).  Most patients responded to fluid and atropine and all but one were discharged within 36 h.

Descriptions of “mad honey” toxicity always make interesting reading, but there is really nothing new in this report.  The authors recommend that stable emergency department patients be monitored for 24 hours; there is nothing in their data that supports this prolonged observation, given that all patients had onset within 4 hours, and previous papers have suggested that 6 h of monitoring is sufficient.