She has also attended Auckland City Hospital's Emergency Department on weekend nights and invited patients affected by alcohol to sign up.
Participants can log in to a website, compose text messages and arrange for them to be sent to their phones at a time when they are likely to be drinking.
An application for iPhone and Windows Phone allows drinkers to add or change the text and schedule from their phone as their plans change.
"The approach we are taking is not an anti-alcohol approach. It's more tackling harm," Ms Renner said. "We all like having a drink or two or three. And that's not going to change any time soon."
The project is ready to enter the second phase of its feasibility study, with early participants choosing a wide array of messages.
"'Go easy' is common ... some are quite specific, along the lines of 'exam time, don't even think about it'. Some are along the lines of 'don't drink too much, you're a bitch when you're drunk'. The whole gamut of aggressiveness."
Previous studies have shown that people reduced drinking after researchers wrote and sent them text messages during drinking sessions.
However, Ms Renner's programme is the first where participants compose the messages themselves - something she feels is important.
"My approach or philosophy is that the person who understands you best is you yourself."
Ms Renner said initial users of the service had used it to target drinking generally and not warned themselves away from specific situations.
She hopes to sign up about 200 participants and depending on the success of the feasibility study, the next stage will be a full trial of the service and its effect on participants.
People can sign up on www.spillitnz.co.nz or text 022 019 9731 for more information.
THE SERVICE
* Drinkers sign up and are sent text messages.
* Use website to write texts themselves, and choose send time.
* Self-service campaign aims to reduce harm from drinking.
