An alleged sword attacker accused of nearly decapitating a schoolboy in a drug-fuelled rampage in London has told of taking psychedelics and drinking his own urine years before amid an interest in spirituality.

Marcus Arduini Monzo, 37, allegedly skinned and deboned his pet cat before launching a 20-minute spree of violence in Hainault, east London, while high on cannabis, the Old Bailey heard.

He is accused of murdering 14-year-old Daniel Anjorin, mowing down pedestrian Donato Iwule with a van and attacking two police officers and a couple in their home on April 30 last year.

Giving evidence on his background on Friday, Monzo told the court he experienced 'bullying and violence' while growing up in Brazil.

He moved to London in 2013, where he began smoking cannabis and took magic mushrooms a few times, jurors heard.