Which sign is NOT associated with a neurotoxic snakebite?

Progressive edema is not typically associated with neurotoxic snakebites. Neurotoxic envenomations primarily affect the nervous system, leading to symptoms such as paralysis and respiratory distress. In cases of neurotoxic snakebites, signs like bilateral ptosis indicate paralysis of the eyelid muscles, descending paralysis illustrates the progression of motor impairment from the head down, and dyspnea along with altered mental status (AMS) reflects respiratory muscle involvement and potential neurological compromise.

On the other hand, progressive edema is more characteristic of local tissue response to venom, which is more associated with cytotoxic or hemotoxic snakes rather than those that primarily exert neurotoxic effects. Hence, recognizing that progressive edema does not align with the primary effects of neurotoxic snakebites helps clarify why this choice is the correct answer.