[citation needed] This may be regarded as advice for people who come across the species in the wild: that is, while P. nuchalis is generally cautious, shy, and inclined to retreat rather than attack, it will defend itself if cornered.

The northern brown snake grows up to 1.8 m (5 ft 10.87 in) in total length (including tail).

[3] Although the northern brown is not an arboreal species, it is not uncommon for it to climb small shrubs or trees.

Pseudonaja nuchalis preys upon small mammals and reptiles, including lizards and mice.

Human symptoms of a northern brown snake bite are headache, nausea/vomiting, abdominal pain, severe coagulopathy, and sometimes kidney damage.