The plant known as the “suicide plant” is infamous for inflicting severe and long-lasting pain. Its sting is considered one of the most agonizing experiences a person can endure from flora. The name reflects the pain’s debilitating nature.
Identifying the Suicide Plant
The suicide plant’s scientific name is Dendrocnide moroides, though it is more commonly known as Gympie-Gympie, stinging tree, or stinging bush. This plant is typically a straggly perennial shrub, often growing between 1 to 3 meters tall, but can reach heights of up to 10 meters. Its distinctive features include large, heart-shaped leaves, measuring 12–22 cm long and 11–18 cm wide, with clearly toothed margins. The leaf stem, or petiole, is notably long and attaches to the underside of the leaf blade, a characteristic known as peltate.
All parts of the plant, including its stem, branches, petioles, leaves, and even its pink to light-purple, globular, mulberry-like fruits, are covered in fine, hair-like stinging structures called trichomes. This plant thrives in rainforest environments across Malaysia and Australia, extending from the Cape York Peninsula south into northern New South Wales. It frequently colonizes disturbed areas within rainforests, such as alongside water courses, roads, and clearings, benefiting from sunlight and soil disruption. The plant is also found in Indonesia and the Moluccas.
The Mechanism of Its Sting
The suicide plant’s microscopic, silica-tipped hairs, or trichomes, are designed to act like hypodermic needles. Upon even the slightest touch, these brittle hairs embed themselves into the skin. Each trichome has a structurally weak point near its tip, which fractures upon skin penetration, allowing the contents of the hair to be injected.
The potent effect of the sting is primarily due to a complex cocktail of neurotoxins. While earlier research identified a compound called moroidin, more recent studies have pinpointed a family of disulfide-rich peptides known as gympietides as the key pain-inducing agents. These gympietides are structurally similar to toxins found in some spiders and cone snails. They effectively activate sensory neurons, interfering with voltage-gated sodium channels to prolong pain signals.
The stable structure of these gympietides contributes to the long-lasting nature of the pain. The plant continuously sheds its trichomes, which can become airborne and cause respiratory irritation if inhaled. The stinging capability persists even in dead leaves or specimens preserved for decades.
Effects of Exposure
Contact with the suicide plant immediately triggers a severe burning and stinging sensation. This pain intensifies rapidly, often peaking within 20 to 30 minutes following exposure. The excruciating pain can persist for extended periods, ranging from hours to days, weeks, or even several months. The pain can recur intermittently, especially with changes in temperature, such as cold showers, or with physical activity, sometimes for up to two years after the initial sting.
Beyond the intense pain, other symptoms include localized swelling, redness, and a rash on the affected skin. Individuals may also experience piloerection (where hairs stand on end) and intense itching. Muscle spasms and aching joints are additional reported effects.
In some cases, the lymph glands, particularly those in the armpits, can swell and become painful. Severe exposures have been documented to lead to shock. While anecdotal accounts suggest extreme outcomes, including death in animals like dogs and horses, and rare human fatalities, one human death was attributed to a related Dendrocnide species, D. cordata.
Handling and Prevention
If accidental contact occurs with the suicide plant, it is important to avoid rubbing the affected area. Rubbing can cause the delicate trichomes to break off and embed deeper into the skin, making them more difficult to remove. The recommended first aid involves using depilatory wax or sticky tape to carefully remove the embedded hairs from the skin. This method was developed by Dr. Hugh Spencer of the Australian Tropical Research Foundation and is widely used for effective hair removal.
Despite these methods, complete removal of the tiny hairs is not always achievable. For severe reactions or persistent pain, seeking medical attention is important. To prevent accidental contact, individuals in areas where the plant is known to grow should wear protective clothing. Learning to identify the plant’s appearance is also a preventative measure. The plant is often found along the edges of forests or roadsides, highlighting the need for vigilance in such environments.