How is euthanasia performed on a dog?

There are several ways to euthanize a dog, commonly injecting potassium chloride or a coagulant, or giving oral sedatives and injectable anesthetics. Potassium chloride blocks heart conduction and makes the heart suddenly stop. A coagulant clots the blood, blocking vessels and blood flow to kill the dog, but anesthesia is given first to put it to sleep and reduce pain.

Another method is to give oral or injectable sedatives first, then inject an overdose of anesthetic to suppress the respiratory system, eventually stopping breathing and causing death.