The autopsy did not conclusively determine the cause of McPherson's death. She had been taking sleeping pills following numerous health problems. Among the pills found in the hotel room was the barbiturate Seconal, a strong sedative which had not been prescribed for her. It was unknown how she obtained them. The coroner said she most likely died of an accidental overdose compounded by kidney failure. The cause of death was listed as unknown. Given the circumstances, there was speculation about suicide, but most sources generally agree the overdose was accidental.