I want to eliminate lizards in my house. What kind of poison can I use?

Depending on where you live, repelling them may do better than poisoning. The cheapest, most effective reptile repellant is napthalene, or plain old mothball flakes. The first time you use it, make sure you leave them an escape route. Come back after they've had a chance to leave, say about three weeks, and go all around your house. You shouldn't need more than three or four applications to teach them your house is not a good place anymore.