Why is snake venom so dangerous?

THAT'S THE WHY:EVERY YEAR, thousands of people lose their lives or limbs following a bite from a venomous snake.

These feared reptiles use toxins to disable prey, and when one sinks its fangs into a human, its venom glands release a complex cocktail of toxic compounds that can subdue, paralyse, induce shock and kill.

The poisons in venom mean business – they can target the nervous and cardiovascular systems, cause rapid drops in blood pressure, delay blood clotting and invoke tissue damage.

Without rapid access to an antidote, such as “envenomation”, a bite can be disastrous for the recipient, but on a broader level some benefit has come out of studying snake poisons.

Their actions in the body have shed light on how particular receptors work, and venom also provides a rich hunting ground for new therapeutic drugs and their targets.

One of the most famous discoveries stems from the 1940s, when a study on venom from the South American pit viper Bothrops jararacateased out the involvement of a peptide called bradykinin in the control of blood pressure in mammals.

Those insights paved the way for the development of ACE inhibitors, a class of drug that is widely used today to treat people with chronic high blood pressure.

And the discoveries have been rolling in ever since. In January the discovery of a neural poison called haditoxin from the venom of the King Cobra was "paper of the week" in the Journal of Biological Chemistry, which stated that "haditoxin might have many future uses in developing molecular probes and therapeutic agents".

– CLAIRE O’CONNELL