What chemicals are used in lethal injection?

The chemicals used in lethal injection can vary depending on the state or country. However, the most common three drugs used in the United States for lethal injection are:

1. Sodium thiopental - a barbiturate used as an anesthetic to induce unconsciousness.
2. Pancuronium bromide - a muscle relaxant that paralyzes the muscles and stops breathing.
3. Potassium chloride - a drug that stops the heart.

It's worth noting that several states have changed their lethal injection protocol due to difficulties in obtaining some of the drugs or legal challenges to the use of certain chemicals. In some cases, alternative drugs or methods have been proposed or utilized.