COPENHAGEN — Danish drugmaker Lundbeck said Friday it would restrict the distribution of its Nembutal drug to prevent its use in lethal injections in US prisons.

"The company has moved to alter the distribution of its medicine Nembutal (the trade name for its pentobarbital sodium injection) in order to restrict its application as part of lethal injections in the US," the Danish company said in a statement.

The drug will from now on "be supplied exclusively through a specialty pharmacy drop ship program that will deny distribution of the product to prisons in US states currently active in carrying out the death penalty by lethal injection," Lundbeck explained.

It said it notified its distributors of the plan in late June.

Lundbeck's pentobarbital anaesthetic is used to treat severe epilepsy but is also used by a number of states as part of a three-drug cocktail used to execute death row inmates.

"We cannot guarantee anything, but we are convinced that our new distribution programme will help to limit the abuse of Nembutal by prisons in their executions. At the same time we ensure patient access to vital treatment," Lundbeck's chief executive Ulf Winberg told the Berlingske daily.

The Danish company had previously said it opposed the use of the drug in lethal injections, but said in March pulling it from the market could result in patients with severe epilepsy being "left without this treatment".

Danish Foreign Minister Lene Espersen said in April she planned to, through the Danish embassy in Washington, address the relevant states with a call for them to stop using Lundbeck's drug for executions.

In lethal injections, pentobarbital anesthetic effectively puts the person to sleep, before a dose of pancuronium bromide paralyzes the muscles and potassium chloride stops respiration.

The Danish government has said it wants to help reduce and ultimately eliminate the use of the death penalty worldwide.