Which painkiller has been responsible for large scale decline in the vulture population?

Diclofenac
On the request of Union Environment Ministry, the Union Health Ministry banned the sale of multiple-dose vials of a painkiller “diclofenac” whose use in the veterinary sector has pushed vultures in India to the brink of extinction. The commonly-used anti-inflammatory drug for cattle is considered the chief cause for the steep decline in the number of vultures in recent years. The drug is harmless to the cattle it is administered to, but is fatal for the vultures, who routinely feed on the carcass of dead cattle. Studies have shown that the drug causes kidney and liver failure in vultures.