The drugs found in Nicola Furlong's system have been ruled out as factors in her death.
The doctor who carried out the autopsy on Nicola's body gave evidence this morning on the second day of the trial in Tokyo, during which he said he believed strangulation was the most likely cause of death.
Nineteen-year- old American musician Richard Hinds has admitted strangling the 21-year-old from Wexford in a hotel last year, but denies killing her intentionally.
It is being reported that remnants of Xanax were found in Nicola's system, as she took it for exams or when flying, and the presence of another drug was also explained in court.
Lidocaine, a local anaesthetic, was applied to a tube when it was put in to Nicola's trachea when she was brought to the hospital on May 25 last year.
The doctor has ruled them out as the cause of death and as date rape drugs.