Makeshift syringes made from cotton buds, prisoners "stoned" for days and drugs secreted inside inmates' bodies.

This was the drug scene inside NSW's Junee Correctional Centre when Anthony Van Rysewyk died from a heroinoverdose in 2011, an inquest has found.

According to correctional officer Steve McMahon, drugs are a problem facing all prisons across the state.

Van Rysewyk was nearing the end of a minimum six years and three months sentence for robbery when he took two shots of heroin at the privately-run facility near Wagga Wagga on May 7, 2011.

In handing down her findings into the 28-year-old's death on Wednesday, Deputy State Coroner Sharon Freund said when Van Rysewyk was put into his cell that evening other minimum security inmates noticed he was slurring his words, was unsteady on his feet and had "pin eyes" - a clear symptom of heroin intoxication.

Correctional service officers reported noticing nothing.

The next morning he was found dead in his cell.

According to inmates who gave evidence at the inquest, legal and illegal drugs - including heroin, marijuana and speed - regularly flowed into the prison.

Inmates regurgitated prescription medications obtained from the centre's pharmacy, while visitors ferried drugs in.

One inmate told the inquest how he had seen a visitor retrieve a parcel "about the size of a golf ball" from her crotch and pass it to a prisoner.

The prisoner then allegedly tried to put it up his anus.

Syringes were constructed from miscellaneous items, including cotton ear-buds as plungers.

"Inmates would be stoned every weekend, every day or Sunday to Tuesday from drugs that were available weekly," Ms Freund said.

Mr McMahon, also the Public Service Association (PSA) chair of prison officers, said drugs were "certainly a problem" in all NSW correctional centres.

"Some prisoners say that they are as easily available in jail as what they are on the streets," he told AAP.

"I don't personally believe that they are that prevalent. (But) there is certainly still a high incidence of drug use in jail."

Mr McMahon said he has found prisoners dead in their cells a number of times over his 20-year career, and pointed to contact visits as the primary way of drugs coming into the centres, with people secreting items into all bodily crevices, including mouths.

He suggested increasing the use of sniffer dogs and improving officers' training to identify drug intoxication.

These were among two of the recommendations also made by Ms Freund.

At the time of Van Rysewyk's death, she said there were only two officers supervising up to 40 inmates at the visitor centre, meaning prisoners were sometimes left unattended for up to five minutes.

There were no CCTV cameras and the dog squad didn't patrol the centre during or after visits.

Improvements at the centre run by GEO Group Australia had been "nominal" since the 28-year-old's death, the court heard.

GEO Group said in a statement it had "already taken steps to address the areas outlined in the recommendations", including conducting a review of officers' training.

Corrective Services NSW (CSNSW) Commissioner Peter Severin said it took Van Rysewyk's death "very seriously" and would be looking at the coroner's recommendations.