US inmate Christa Pike says she woke up 'confused and in pain' after failed execution

US death row inmate Christa Pike has released her first public statement since her botched execution in September.

"There hasn't been a moment since that night when I haven't been in pain," she said in a statement released by her legal team on social media on Friday.

"My body hurts. My arms hurt. My hands hurt. My throat hurts. I still struggle to speak. And the pain isn't just physical. There is pain in my mind and in my soul."

Pike, 50, was discharged from hospital at the end of last month after surviving two lethal injections of the drug pentobarbital, which left her in a critical condition.