Police were called when an agoraphobic boozer, who spray-painted obscenities on the wall of his elderly mother's Nottinghamshire house, was accused of wielding a knife.
But when police searched Craig Garton's bedroom, in his mum's Boughton home, on January 11, they found a small amount of MDMA instead.
"His mother said he had become aggressive and thrown his dinner against the wall and wielded a knife," said prosecutor Daniel Church.
"His mother said: "I am 80 years old. I don't need this. I want the defendant to leave me alone.""
He said Garton had also kicked the bedroom door, causing the veneer to separate from the frame.
Garton, who admitted being drunk at the time, tested positive for cocaine, but missed a follow-up appointment in Newark on January 22, and a court appearance on February 21.
Mr Church said Gardton has 17 convictions for 33 offences, and was last in court in 2017.
Michael Little, mitigating, said her client suffers from agoraphobia, which prevents him leaving the house, but had made attempts to contact the court.
He said Garton has long-term alcohol problems and intermittently uses drugs. The MDMA had been given to him on New Year's Eve, and he had forgotten about it.
He had since paid a handyman to fix the door and paint the wall, Mr Little added.
Garton, 54, now of Derby Road, Sandiacre, admitted criminal damage, possession of the Class A drug, and the two Bail Act offences, when he appeared at Mansfield Magistrates Court, on Thursday.
He received an 18 month conditional discharge, with £85 costs and a £20 government surcharge.
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