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TWO US states are considering using the synthetic painkiller fentanyl as part of the cocktail of drugs used to execute prisoners on death row.

Many pharmaceutical firms have stopped supplying prisons with the drugs used in lethal injections. Nevada and Nebraska are both proposing to add fentanyl to the mix to get around this, as it is much easier to access.

The opioid drug is used clinically to treat severe pain, such as that of advanced cancer. It works in the same way as heroin, but is 50 to 100 times more potent – …