Russell Bullivant, 51, was high on a cocktail of methadone and the anti-anxiety/seizure drug Lyrica when he got behind the wheel of his vehicle on the afternoon of March 10 and tried driving along Cotterill Avenue.

Court documents said Bullivant ran off the road on a right hand bend, mounted the gutter and continued into the front lawn of one of the properties, where the owner was moving pavers.

The vehicle hit the woman and pinned her against a disability ramp at the front of the home.

Bullivant reversed the vehicle and left the scene without checking on the victim or giving her his details.

Meanwhile, the woman's daughter came out of the house after hearing the commotion.

She used her phone to photograph Bullivant and his car as he drove off.

The victim was taken to Wollongong Hospital and treated for bruising and swelling but was otherwise unhurt.

Police attended a house in Woonona an hour later and discovered Bullivant hiding under a bed.

The officers said Bullivant was slurring his speech, mumbling his words and couldn't hold a conversation without falling asleep.

"He couldn't hold his head up to look straight ahead, his eyes were constantly closing and he was struggling to stay awake just to talk," the officers said in court documents.

"He couldn't walk, was swaying, stumbling and needed assistance so he didn't fall down."

The court heard Bullivant told police he'd recently used methadone and Lyrica.

Bullivant was charged with driving under the influence of drugs, negligent driving and failing to give particulars to an injured person.

He pleaded guilty to all three charges in court on Tuesday. The case was adjourned for a background report to be prepared ahead of Bullivant's sentencing on October 27.