# How does the time to die from venom change for very large organisms?

Let's say that an untreated snakebite kills a human in 2-3 days.

Now consider a much larger mammal, such as a blue whale. If a proportional amount (equal chance of lethality) of the same venom was injected into the whale, roughly how long would the whale take to die?

I'd assume it would take longer because the whale is larger so it would take longer for the venom to diffuse, but I don't know the specifics. Just looking for a ballpark; are we talking 2-3 days for the whale as well? Or weeks? How does dimensional analysis work for venom diffusion?

• It might not kill the whale at all, depending on the nature of the venom. I suspect this is because toxins are not magically poisonous; check out median lethal dose on wiki.
– Tom
Commented Apr 15, 2022 at 0:02
• I can finish 3 or more chocolate bars without admitting to a&e but it took only one bite to finish my chihuahua. Commented Apr 15, 2022 at 6:22
• I shouldn't have to mention that we're talking about a venom that's equally lethal to the whale (in the dose given to the whale) as to the human (in the dose given to the human). Commented Apr 15, 2022 at 13:11
• @causative As a general rule on worldbuilding it's better to over-specify instead of leaving things vague and undefined. We don't know anyone's level of knowledge and the last thing you want in an answer is someone relying on an incorrect assumption about your world while writing an answer. You may know that you're already factoring in how different species respond differently to different but if we don't, since differing biologies will matter a lot more than size, we'd be failing if we didn't mention that fact. Commented Apr 15, 2022 at 17:16

It's going to depend on the specific mechanism of lethality.

First off remember that different animals respond very differently to the same poisons. If I eat a red eft I'm going to have a bad but probably not lethal time. A garter snake on the other hand will happily chow down on one and go back for seconds. For the record I'm much much larger than a garter snake.

If something kills by spreading localized tissue death, then a larger critter poisoned in an extremity may be able to survive longer.

If something kills by preventing your muscles from relaxing, as soon as that gets near a critter's heart there aren't going to be many heartbeats left. All blood is constantly getting recirculated through the heart. Regardless of size once a poison gets into the blood it's going to quickly end up there.

There are many mechanisms of action for various venoms, all with very different lethal doses. Some animals especially when acting defensively will deliver far more than the minimum lethal dose. You're going to need to do more research, or come back asking a more specific question to be able to say for sure what will happen. Or you can make up an answer that makes sense for your narrative.