The stresses of NSW emergency departments are prompting medical professionals to prescribe addictive opioids for acute back pain when other treatments are more suitable, a new study has shown.

The University of Sydney-led trial involved almost 4500 patients at four NSW hospitals - three in greater Sydney and one in Dubbo.

It involved training about 300 medical professionals in assessing and treating patients with acute back pain without prescribing opioid medication.

The clinicians in the trial provided alternative treatments such as non-opioid medication, heat wraps and referring patients to physiotherapy.

Researchers found that across the four hospitals, there was a 12 per cent decrease in opioid use to treat cases of acute back pain.

This occurred with no increase in pain levels or drop in patient satisfaction.

Lead study author Gustavo Machado said in a statement that opioids were often prescribed as a quick, short-term fix but then become addictive.

"Emergency departments are incredibly busy places and there is a huge pressure on clinicians to treat people as quickly as possible," Dr Machado said.

"Our trial has demonstrated that there is a safer way to treat acute back pain that can easily be adopted by hospitals across the country."

At Canterbury Hospital in Sydney's southwest alone, there was a reduction of up to 24 per cent in opioid prescriptions issued to patients.

Canterbury Hospital medical services director Eileen Rogan said the trial demonstrated a better way to alleviate acute back pain.

"Our physicians and nurses embraced this trial because they could see the positive results almost immediately," Dr Rogan said in a statement.

"Patients were happy - they were receiving better care in the emergency department, getting follow-up care if needed and there was an important drop in the amount of opioid painkillers used."