What type of poison are pyrethroid pesticides classified as?

Pyrethroid pesticides are classified as nerve poisons because they target the nervous system of insects. These compounds function by disrupting the normal transmission of nerve impulses, leading to paralysis and death of the insect. This mechanism is achieved through the modification of sodium channels in the nerve cell membranes, causing them to remain open longer than they should.

While skin irritation can occur with some pyrethroids, their primary action is on the nervous system, making the classification as a nerve poison more accurate. Similarly, respiratory depression is not the main concern with pyrethroids, as they primarily interfere with the neural functions of pests rather than directly affecting respiratory processes. Though "neurotoxin" might seem like a suitable descriptor given their effect on the nervous system, the term nerve poison more succinctly captures their intended action and application in pest control.