A patient at Kyushu University Hospital in Fukuoka who died in March was administered the wrong medicine by a nurse during treatment in August last year, hospital officials said Thursday.

In a news conference Thursday, the officials admitted to the mixup but stressed that the man's death was "not related to that."

The man, in his 50s, was first admitted to the state-run hospital in December 1998 to undergo treatment for a blood cell disorder, according to the officials.

After receiving a bone marrow transplant from a relative, he had to be given an antiviral drug in August last year because of the emergence of herpes zoster, officials said.