‘Mad honey’ that can stop your heart is now being sold online worldwide
Honey hunters in Nepal scale incredible heights to harvest the honey of the Himalayan cliff bee. Skanda Gautam/SOPA Images/LightRocket via Getty Images A few months ago, a friend of mine told me that his father-in-law had been rushed to the hospital after eating some wild honey brought back from the hills of Nepal.
Mad honey is a type of wild honey produced by the Himalayan cliff bee, Apis laboriosa, which lives in the high Himalayas at altitudes up to 13,000 feet (4,000 meters). This honey contains a natural toxin called grayanotoxin, which comes from the rhododendron flowers the bees collect nectar from. The toxin is concentrated in the honey, making it potentially dangerous for humans. Eating a small amount, about a teaspoon, may cause mild effects like warmth or light-headedness, but consuming more can lead to severe health issues, including a dangerously slow heart rate and collapsing blood pressure. The name 'mad honey' comes from these hallucinogenic and toxic effects. Historically, indigenous Gurung people of Nepal have harvested this honey safely for centuries, but modern knowledge of safe consumption is now being lost as the honey is sold internationally.
The Himalayan cliff bee collects nectar from rhododendron flowers, which contain grayanotoxin, a chemical the plant likely evolved to deter insects that steal nectar without pollinating. The bees store this toxin in their honey, though scientists do not fully understand how the bees tolerate it. For humans, grayanotoxin interferes with the heart muscle’s ability to generate electrical signals, slowing the heart rate to dangerous levels. Symptoms of poisoning include dizziness, nausea, weakness, and a drop in blood pressure within 30 to 60 minutes of consumption. While the bees are unaffected, the toxin can hospitalize a human after just a few tablespoons. The concentration of grayanotoxin varies by season, location, and rhododendron species, making the honey’s potency unpredictable.
A study reviewing 68 poisoning cases from 27 published papers between 2009 and 2026 found that 72% of patients were middle-aged men who ate the honey deliberately, not accidentally. Many were using it as a traditional home remedy for high blood pressure or to improve sexual function, practices passed down through generations in Himalayan communities. While small amounts of mad honey may lower blood pressure—supported by rat studies—the gap between a safe dose and a toxic dose is very narrow and varies by batch. Poisonings peak in spring during the main honey harvest, when rhododendron flowers are in full bloom and toxin levels are highest. A smaller wave of cases occurs in autumn during the secondary harvest. Most patients recover within a day or two with treatment, such as intravenous fluids and the drug atropine, which restores normal heart rhythm.
Mad honey is now being sold online worldwide, often marketed as a psychoactive superfood with prices reaching several hundred U.S. dollars per kilogram. However, sellers frequently omit warnings about safe consumption amounts, and buyers may underestimate the risks. Poisoning cases have already been documented in countries like South Korea (15 cases in 2013), France, and Qatar, where doctors are unfamiliar with the condition. Patients may not mention eating mad honey, delaying diagnosis and treatment. The lack of awareness about its dangers, combined with its high price and exotic appeal, has turned a local tradition into a global public health concern. The article highlights the need for better education and regulation to prevent unintended poisonings.
Despite the documented cases, there is limited research on the chemical ecology of mad honey. Scientists plan to test honey samples from different regions and seasons in Nepal to measure grayanotoxin levels and identify which rhododendron species produce the most toxin. They also aim to study how the bees tolerate the toxin, a mystery that fascinates researchers. Additionally, the Himalayan cliff bee population is declining due to overharvesting, habitat destruction, and climate change, raising conservation concerns. This bee plays a crucial role in pollinating high-altitude plants, including rhododendrons, and its decline could disrupt the ecosystem. Scientists lack baseline data on insect populations in the Hindu Kush Himalayan region, making it difficult to assess the rate of change and implement effective conservation strategies.
