Governments should help us quit smoking and not call us criminals for choosing e-cigarettes.

After 35 years of smoking and a dozen failed attempts at quitting, Angela Gordon finally kicked her addiction - but she's become a criminal in the process.

The 54-year-old nurse had been smoking since she was 12, trying patches, gums, inhalers and the medication Champix to drop the habit that drove her to smoke more than 40 cigarettes a day, making her increasingly ill in the meantime.

The Champix gave her suicidal thoughts and the rest were useless, until four years ago when she ordered an e-cigarette online from overseas.

She hasn't picked up a cigarette since, and her doctor now considers her a former smoker.

"Unfortunately my government considers me a criminal."

The nicotine Ms Gordon uses in her e-cigarettes is classified as a Schedule 7 "dangerous poison" - the sale and possession of which is illegal.

To make matters worse she's also become a trafficker, selling the product to a neighbour with early stage emphysema who quit smoking within two weeks of trying the e-cigarette.

A Senate inquiry into nanny state laws is conducting a public hearing on e-cigarettes in Sydney on Wednesday, with several former smokers giving evidence that "vaping" safer e-cigarettes has helped them kick long-term smoking habits.

Ms Gordon says complying with nanny state laws on e-cigarettes would mean taking her neighbour a carton of cigarettes and helping to advance her emphysema.

"My crime is that I quit smoking the wrong way," she told the hearing.

Drug reform advocate Alex Wodak, director of the St Vincent's Hospital alcohol and drug service, said e-cigarettes were far safer and cheaper than cigarettes, describing them as a "significant economic boon" to smokers as well as taxpayers.

He dismissed claims that legalising nicotine vaping would encourage smoking.

New Nicotine Alliance, a not-for-profit group that advocates nicotine products as a safe alternative to smoking, said existing laws were protecting big tobacco companies.

The penalties for importing and using liquid nicotine are similar to possession of heroin in some states, they say.

Legalising nicotine e-cigarettes could make smoking obsolete, save lives, earn the government more tax revenue and slash health costs.

"This goes far beyond the nanny state, this is the monstrous state," president Dr Attila Danko said.