Melbourne researchers combed a decade of Victorian coroners' data and found 115 cases in which codeine and ibuprofen were both detected, including 63 examples in which drug toxicity was the cause of death.

Nine cases between 2001 and 2011 could be directly linked to the internal damage caused by long-term misuse of the tablets, including gastric erosions and ulceration.

There are a number of painkillers on the market in Australia that contain ibuprofen and codeine. At  12.8 milligrams of codeine, Nurofen Plus is one of the tablets that contain the highest available dose of codeine for an ibuprofen-combination tablet. Others brands include Pharmacor Ibuprofen Plus, ProVen Plus, Rafen Plus, Panafen Plus and Chemists' Own Ibuprofen Plus Codeine.

Some people have been known to take up to 100 tablets a day, travelling from chemist to chemist to fuel their habits. Despite 2010 laws limiting the size of doses available, the reports of misuse are only increasing.

Jennifer Pilgrim, a researcher at Monash University's Department of Forensic Medicine, co-authored the new study and explained that while ibuprofen was the ingredient that caused deaths it was the codeine that created addiction.

It is for that reason experts including a senior medical adviser with the Victorian government have called for the pill to be restricted to prescription-only or for codeine to be banned from over-the-counter products. Dr Pilgrim said the other alternative was for chemists to monitor the quantity of drugs bought by each person. ''All those options involve more input from prescribers and the pharmacist, but that is the only way the situation is going to be managed,'' she said.

In one case, a 48-year-old woman who died after abusing Panafen Plus had already been identified as a doctor shopper and had restricted access to prescription medicines. But Dr Pilgrim said she was still able to travel to multiple chemists to gather large quantities of codeine.

''The coroner actually made a point of saying the problem in this case is the drugs that she can access over the counter quite easily were the ones that killed her,'' Dr Pilgrim said.

The clinical director of Melbourne's Turning Point Alcohol and Drug Centre, Matthew Frei, continues to lobby for larger warnings on packets. Last week he came across one of the most extreme cases of over-the-counter codeine abuse he had seen, a man in hospital for low potassium who was taking more than 100 tablets a day.

Dr Frei said those addicted to the pills often had a similar story. Many became hooked after starting to take the tablets for legitimate pain.

Mulwala man Travis Rowe is on a rehabilitation program after a 10-year Nurofen Plus addiction that resulted in him being sent to prison for 13 months because he often drove unlicensed to visit chemists in other towns in NSW and Victoria.

Mr Rowe, 43, started taking Nurofen Plus when he had a sore shoulder, but his habit escalated to 50 tablets a day after he lost his job. The addiction cost him $400 every week in pills alone.

''Now I can spend time with my kids, my yard looks good, I don't have blues with my missus,'' he said.

The Australian Self Medication Industry, a healthcare products lobby group, said it had been looking at ways to support safe use of codeine-combination products, including label warnings. However, it said it was important to keep in mind most people used the medication appropriately.

An earlier version of this story said Nurofen Plus is the strongest codeine tablet available without a prescription in Australia. This is incorrect. It’s among the strongest codeine-ibuprofen tablets available without a prescription in Australia. The text has been changed.