The Truth About Eye Bleeding
The vivid image of bleeding from the eyes after a snakebite is a dramatic notion, often seen in fiction. In reality, literal bleeding from the eyes is not a typical symptom of snake envenomation, and is largely a misconception.
While blood may not pour directly from the eyes, severe snakebites can lead to widespread internal bleeding throughout the body. This systemic hemorrhage can affect various mucous membranes, including subtle bleeding in or around the eyes, such as subconjunctival or retinal hemorrhage. These effects are a consequence of the venom’s systemic impact on the circulatory system, not a direct attack on the eyes.
How Potent Venoms Affect the Body
Snake venoms are complex mixtures of proteins and enzymes designed to incapacitate prey and aid in digestion. These potent compounds interact with the victim’s body in different ways, leading to a range of severe symptoms. The primary categories of snake venom are hemotoxic, neurotoxic, and cytotoxic, each with distinct mechanisms of action.
Hemotoxic Venoms
Hemotoxic venoms primarily affect the blood and circulatory system. They disrupt the body’s clotting mechanisms, which can result in widespread internal bleeding. This bleeding is characterized by oozing from the bite site, nosebleeds, bleeding gums, and extensive bruising.
Neurotoxic Venoms
Neurotoxic venoms target the nervous system, interfering with nerve impulses. Symptoms include muscle weakness, drooping eyelids, difficulty moving the eyes, blurred vision, and slurred speech. The most serious effect of neurotoxic envenomation is paralysis of the respiratory muscles, which can lead to respiratory failure if untreated. Unlike hemotoxic venoms, neurotoxic venoms do not cause significant bleeding or tissue damage at the bite site.
Cytotoxic Venoms
Cytotoxic venoms cause localized tissue damage and cell death. This leads to immediate burning pain, swelling, blistering, and destruction of skin and muscle tissue at the bite area. In severe cases, extensive tissue necrosis can occur. While primarily localized, the breakdown of muscle cells can also lead to kidney damage.
Snakes Known for Extreme Envenomation
Certain snake species are known for venoms that cause severe systemic effects, particularly those that lead to widespread internal bleeding or multi-organ damage.
The Boomslang (Dispholidus typus), an arboreal snake found in sub-Saharan Africa, possesses a potent hemotoxic venom. Its venom disrupts the blood clotting process, leading to massive hemorrhage that can manifest as bleeding from gums, nose, and internal organs. Symptoms can be slow to appear, sometimes taking hours for significant effects to become apparent.
Another group of snakes known for causing severe internal bleeding are certain vipers, such as the Russell’s viper (Daboia russelii) and saw-scaled vipers (Echis carinatus). Russell’s viper venom can cause severe pain, swelling, and bleeding due to blood clotting problems. This can lead to internal hemorrhages, kidney failure, and other organ damage. Saw-scaled vipers, despite their smaller size, inject a potent venom that also causes significant coagulation defects and hemorrhage. These effects can result in major internal bleeding and kidney issues if not promptly treated.
Responding to a Severe Snakebite
A venomous snakebite is a medical emergency that requires immediate attention. The primary step is to call emergency services or transport the person to the nearest hospital without delay. Rapid medical intervention, especially the administration of antivenom, improves outcomes and can be life-saving.
While waiting for medical help, remain calm and keep the bitten limb as still as possible. Remove any jewelry or tight clothing from the affected area, as swelling can occur rapidly. Gently wash the bite site with soap and water if available. Avoid harmful first aid measures such as applying a tourniquet, cutting the wound, attempting to suck out venom, or applying ice, as these actions can worsen the injury or hasten venom absorption. Antivenom works by neutralizing the venom’s effects in the body.