Which drug is commonly used for euthanasia in animals?

Sodium pentobarbital is the drug commonly used for euthanasia in animals due to its rapid action and ability to induce a deep level of anesthesia leading to a humane death. It works by depressing the central nervous system, resulting in loss of consciousness and subsequent cessation of respiratory and cardiac functions. This makes it a preferred choice for veterinarians when performing euthanasia, as it provides a quick and painless end to the animal's life, aligned with ethical practices in veterinary medicine.

Phenobarbital, while a barbiturate, is primarily used for the management of seizures and not specifically for euthanasia. Succinyl choline is a neuromuscular blocker used mainly for anesthesia induction; it does not provide analgesia or sedation and is therefore unsuitable for euthanasia. Ketamine, an anesthetic agent, is used for sedation and pain relief but does not accomplish the humane death goal on its own. Therefore, sodium pentobarbital is the appropriate and commonly utilized agent for euthanasia in veterinary practice.