Lewisite (L) is classified as a:

Lewisite (L) is classified as a blister agent because it primarily causes severe irritation and damage to the skin and mucous membranes upon contact. This chemical warfare agent was developed in the early 20th century and is known for its ability to produce painful blisters and tissue destruction. Unlike nerve agents, which disrupt the nervous system, or choking agents, which primarily affect the respiratory system, Lewisite's effects are localized to the skin and eyes, leading to blisters and potentially serious long-term health issues. Therefore, its designation as a blister agent reflects its specific mechanism of injury and the symptoms it induces in exposed individuals.