A man who pushed a former Eurotunnel boss on to Tube tracks had taken £600 worth of crack cocaine the day before, the Old Bailey heard.
Paul Crossley shoved Sir Robert Malpas, 91, at Marble Arch in April 2018, having earlier tried to push another man at Tottenham Court Road.
The court heard Crossley had not taken his medication for schizophrenia.
Crossley, 47, of east London, is being sentenced after being found guilty of two counts of attempted murder.
Sir Robert was rescued by bystander Riyad El Hussani, who leapt from the platform to pull him away from danger as a train approached.
The former industrialist, who was knighted in 1998, spent more than a week in hospital with a fractured pelvis and a head wound.
The attack came shortly after Crossley, from Leyton, had tried to push Tobias French onto the tracks at another station.
During his trial, he said he meant “to scare” Mr French, who had “looked at me a bit funny”.
Crossley, who has paranoid schizophrenia, was chased and detained by members of the public after the attack on Sir Robert.
At the sentencing hearing, prosecutor Benjamin Aina QC said: “When the defendant was arrested he simply said: ‘I’ve had no sleep’ – he later said he was diagnosed with paranoid schizophrenia when he was 17.
“He was supposed to be taking medication for mental illness, but he had not taken any medication on that day.
“He had been using crack cocaine the day before the incident – around £600 worth.”
Mr Aina said Crossley “began to hear voices and was getting paranoid” when on the platform.
Crossley told psychiatrist Dr Anneka John-Kamen he remembered thinking “I’m going to hurt someone,” and was anxious because people he owed drug money to were threatening him.
The sentencing hearing is due to conclude on Monday.