Take a few grams of my epilepsy med, and it will kill you no matter how much you weigh. That’s why a couple states misused it for the death penalty.

Take proper dosages and you get different effects depending on dosage (in lowering dosage anticonvulsant, sleep, hypnotic).

Pump that lethal dosage into our water tower and you won’t get anything at all except a homeopathic remedy.