Lotion takes a bite out of snake venom

For a person who has the rotten luck to get bitten by a poisonous snake, every second counts. That’s because venom can spread quickly from the site of the bite to the rest of the body, causing pain, suffering — even death. Australian scientists now have found a way to give snakebite victims more time to get help.

A team identified a lotion that can delay the spread of some venoms. In a new study, the researchers show that when the lotion is applied near the wound shortly after a snakebite, the poison travels more slowly through the body.

“This treatment might make all the difference between dying on the road and getting to the hospital in time,” David Warrell told Science News. Warrell, a physician and retired professor of tropical medicine at the University of Oxford in England, was not involved with the study.

The lotion doesn’t work for all types of snake venoms. In the new study, the scientists show that it can help people who’ve been bitten by the eastern brown snake, a particularly poisonous serpent found in Australia.

Eastern brown snakes have small heads, can grow up to seven feet long and are members of the cobra family. One bite can be deadly. “It’s particularly nasty, one of the most toxic things in the world,” Dirk van Helden told Science News. Van Helden, a physiologist at the University of Newcastle in Australia, worked on the new study.

Some molecules of poison from snakes — like the eastern brown snake — are too large to squeeze through blood vessel walls and into the bloodstream. Instead, these bigger molecules indirectly enter the bloodstream by hitching a ride with the lymphatic system. Lymph is a clear fluid that transports white blood cells throughout the body. Lymph travels through lymphatic vessels until it drains into blood vessels. Molecules of poison can get into these lymphatic vessels and travel with the lymph, eventually winding up in the bloodstream.

The venom-slowing lotion contains nitric oxide, which retards the spread of venom by slowing down the lymphatic system. Nitric oxide is a chemical compound made of nitrogen and oxygen. This compound is often used to treat angina, which is chest pain caused when the heart doesn’t receive enough blood. In the new experiment, the compound was used to slow down the lymph vessels, which in turn would slow the spread of the poison.

In the laboratory, the scientists tested their concoction on 15 human volunteers (who were not required to get snakebites). Each volunteer received an injection of a harmless substance in his or her foot — this was a simulated, or faked, snakebite. The substance took 13 minutes to travel to the groin area. But that time increased to 54 minutes when the volunteers applied the lotion to the “bite site” shortly after the injection. This means that snakebite victims would have more than half an hour longer to get help.

Unfortunately, the new lotion won’t work against all snake venoms. The poison of the black mamba, for example, contains small particles that can more easily slip into the bloodstream. But for people who might come in contact with the eastern brown snake, the cream could be a lifesaver.

POWER WORDS (adapted from the New Oxford American Dictionary)

molecule A group of atoms bonded together. A molecule is the smallest fundamental unit of a chemical compound.

atom The basic unit of a chemical element.

venom Poisonous fluid secreted by animals such as snakes and scorpions and typically injected into prey or aggressors by biting or stinging.

lymph A colorless fluid containing white blood cells that bathes the tissues and drains through the lymphatic system into the bloodstream.

physiologist A biologist who studies the chemical and physical functions of living things.