Making e-cigarettes available on prescription would reassure doctors and patients that they are less harmful than smoking, a leading health expert has told MPs.
Deborah Arnott, chief executive of Action on Smoking and Health (Ash), said there were still misconceptions about vaping despite evidence it was "substantially less harmful" than using cigarettes.
Licensing the products as medical quitting aids would allow them to be promoted and prescribed, she told the Commons Science and Technology Committee.
Last month, Public Health England (PHE) said there was "compelling evidence" e-cigarettes should be made available on the NHS due to their success in helping people stop smoking.
The body said e-cigarettes were at least 95% less harmful than smoking and estimated they could be contributing to 20,000 new quits each year.
Ms Arnott told MPs: "We are pleased that there's a consumer product regulatory system that doesn't seem to be undermining e-cigarette use.
"However, we think there would be considerable benefits in having licensed medicinal products on the market. Unless you have a licensed product, it can't be promoted and advertised and put on prescription for quitting smoking."
She added: "We know that it would reassure doctors, and the British Medical Association has said it would be helpful. We have doctors saying to us all the time, if we had products we could prescribe and that were licensed, we would feel much more comfortable. And they would be effective on prescription and highly cost-effective. These are cheap products which are highly effective in helping smokers quit. It would be reassuring to consumers as well as to medical professionals."
Understanding among adults about the relative harm from vaping has improved over the last year, according to a new survey of more than 12,000 adults by Ash.
Aalf (50%) correctly identified that vaping is less harmful than smoking in 2018, compared to 43% in 2017.
But a quarter (25%) said they believe vaping is as or more harmful than smoking - around the same number as last year.
Hazel Cheeseman, director of policy at Ash, said pregnant woman also needed to be more confident using e-cigarettes as an alternative to smoking.
She told the committee that many worried about vaping in public due to social stigma.
She said: "They need to be given the advice, that all the evidence we have suggests that using an e-cigarette will be safer than continuing to smoke.
"Without this advice, our concern is there is a risk women might revert to smoking. Women need to have confidence in these products that they are a safer alternative, if they are going to be encouraged to use them sufficiently."
The Commons Science and Technology Committee is examining the impact of electronic cigarettes on human health, including their effectiveness as a stop-smoking tool, and the suitability of regulations guiding their use.