Texas will join a handful of states that use a single drug in lethal injections, the Texas Department of Criminal Justice announced Tuesday. 

"Implementing the change in protocol at this time will ensure that the agency is able to fulfill its statutory responsibility for all executions currently scheduled," TDCJ spokesman Jason Clark said in an email.

For Yokamon Hearn's scheduled execution on July 18, officials plan to administer a lethal dose of pentobarbital instead of the three-drug cocktail that has been used since Texas reinstated the death penalty in 1982. Clark said the decision to change the protocol came because the state's supply of one of the other drugs that had been used in the protocol — pancuronium bromide — had expired and TDCJ was unable to obtain more.

"The agency currently has an adequate supply of pentobarbital to carry out all scheduled executions," Clark said. Currently, nine inmates are scheduled to be executed between July 18 and Nov. 14. Clark said that courts have upheld the use of the single-drug protocol as constitutional.

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Pentobarbital is a barbiturate that is often used in animal euthanasia, but states began using it more widely in lethal injections last year. Ohio was the first state to switch to the single-drug protocol using pentobarbital in March 2011. 

Illinois-based Hospira Inc. sent Texas and other death penalty states scrambling last year when it announced in January that it would stop selling sodium thiopental, part of the three-drug cocktail used for lethal injections in Texas, which Hospira had planned to manufacture the drug in an Italian plant, but authorities in that country wanted a guarantee that the drug would not be used in executions. 

But pentobarbital has had some of the same troubles as sodium thiopental. The drug was previously only available from one company operating in the United States, Lundbeck Inc., based in Denmark, a country that also opposes the death penalty. Lundbeck had asked states not to use the drug in executions.

Last year, Lundbeck sold pentobarbital, along with two other products, to Illinois-based Akorn Inc. but required restrictions on the use of the drug in executions to continue.

The Austin American-Statesman reported last month that the TDCJ stockpiled supplies of pentobarbital last spring when concerns about the supply of death penalty drugs arose around the country.

Editor's note: This story initially reported erroneously that Lundbeck Inc. sold the drug pentobarbital. That company sold the product to a different company, and the story has been corrected.

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