What factor causes the potency of the poisonous toxins in the snake to potentially fluctuate?

Answer

What the snake has consumed recently

The poisonous aspect relies on toxins sequestered from its diet; therefore, the potency can fluctuate based on what the snake has eaten recently.

What factor causes the potency of the poisonous toxins in the snake to potentially fluctuate?
Poisonanimalreptilesnake