The most lethal drugs are the legal ones, according to the state's oldest practising drug and alcohol nurse, Thirroul's Jan Ryan.
The 77-year-old, who will retire on Friday, has helped people with addictions to cocaine, heroin, crystal meth and more, yet she said alcohol and tobacco remained the two biggest killers.
"Alcohol and tobacco are still the drugs associated with the most premature deaths, even with the rise of drugs like ice," she said.
"Alcohol, in particular, causes far-reaching damage not only to the individual but to the community through its involvement in domestic violence, assaults and road accidents."
Mrs Ryan graduated as a registered nurse in New Zealand in 1958 and worked in a hospital operating theatre before coming to Australia in 1973.
She moved into community health before making the switch to drug and alcohol nursing in 1988, and has been working for the Illawarra Shoalhaven Local Health District Drug and Alcohol Service since 1995.
"There's been many changes in this area of nursing since the late 1980s - from changes in the treatments available to changes in the way we counsel people," she said.
"We used to use a more confrontational style to get people to admit they had a problem but now we use a more motivational approach to encourage and support people.
"New drugs have emerged and drug use has changed, too - while people used to just have one drug dependence, we are now seeing more polydrug use, where people use two or more drugs at the same time."
Mrs Ryan is part of the withdrawal management team and also works with hospital patients who have drug and alcohol issues.
"Working with addiction has been both challenging and rewarding - it's great to support people to make changes and it's very satisfying to watch them get back on track," she said.
"It can also be quite humbling because people are putting a lot of trust in you and they're sharing their life stories with you."
As the oldest practising drug and alcohol nurse in NSW, and possibly Australia, Mrs Ryan said the key was to look after your own health, too.
"I go to the gym and watch my weight - if you don't take care of yourself then how can you take care of others?" she said.
In retirement, she would be looking forward to "not getting up before the sun" to fit in a gym class before work and to spending time with her husband, four children and nine grandchildren. She would, however, miss her colleagues.
"I have worked with a wonderful, dedicated team of nurses, doctors, psychologists and social workers who support patients and their families," she said. "It has been a privilege to work in this area of nursing."