The toxin allegedly used in the poisoning of Alexei Navalny is not from a dart frog but rather a nerve agent from the Novichok group novichok agents are highly potent organophosphorus compounds developed in the Soviet Union during the Cold War they disrupt the nervous system by inhibiting the enzyme acetylcholinesterase leading to a buildup of neurotransmitters and causing muscle paralysis respiratory failure and potentially death if untreated