Why is rat poisoning an ingredient in crystal meth?

Rat poisoning, specifically the active ingredient known as anticoagulants like bromadiolone, is sometimes used in the production of crystal meth to enhance the drug's effects. It can also serve as a cheap filler or cutting agent to increase the yield of the final product. However, using such toxic substances poses significant health risks to users, as they can lead to severe poisoning or other serious health complications. The presence of rat poison in illicit drugs highlights the dangers and unpredictability associated with street drugs.