The Texas Tribune posts, "Timeline: A History of Lethal Drug Use in Texas," by Terri Langford, Alex Duner and Jessica Hamel. There are infographics and a video at the link.
For nearly 30 years, Texas used the same three-drug lethal injection cocktail to execute death row inmates: sodium thiopental, an anesthetic, followed by pancuronium bromide, a muscle relaxant, and then potassium chloride, which brings about cardiac arrest.
Drug manufacturers in the U.S. and abroad began cutting off supplies in 2011, refusing to allow their use in executions. The dwindling supply set in motion a national scramble among death penalty states, including Texas, to find drugs that could be used to administer the ultimate punishment.
Relying on news stories and TDCJ documents provided to death row inmates' attorneys, The Texas Tribune compiled a timeline of TDCJ’s drug purchases and its use of execution drugs since 2011.
Earlier coverage of Texas lethal injection issues begins at the link.