Every once in a while, Kotrina Lockard’s cell phone buzzes with a text message — a message of inspiration.

The first time, she read these words on the phone’s screen: “Feeling light-hearted? You’re not a ticking time bomb anymore. 20 mins after you quit smoking cigarettes, blood pressure returns to normal.”

Eight hours later, she got another message, informing her that her blood oxygen level would return to normal eight hours after she stopped smoking cigarettes.

Lockard, 31, signed up for the text messages from the Rhode Island Department of Health (by texting “QuitNow” to 75309) in the hope they might help her quit smoking cigarettes again. She’d been able to quit while pregnant, but resumed after her baby was born. Now, the stress of unemployment has made such a wrenching life change all the more difficult for the Providence mother.

The text messages are providing an important nudge forward, she says. “It’s making me think more about quitting,” she says. “But it’s hard. It’s hard to quit!”

It is hard, and the Health Department’s tobacco-control program, working on a shoestring, is trying everything it can to encourage and support smokers who want to stop. That includes venturing into the burgeoning new field of “mobile health,” an unproven but promising way to improve health through cell phones.

Some 85 percent of Americans own cell phones, according to the Pew Internet and American Life Project. That means the reach of any mobile phone effort is potentially huge, especially among urban, lower-income people who often have poor access to health information.

Thousands of commercial smart-phone applications enable people to track their exercise routines, blood glucose, asthma symptoms or food intake. Public health officials are also tapping into this market.

But what can a mere text message do?

“It’s an incredibly limited tool,” says Dr. Nathan Cobb, research investigator at the Schroeder Institute for Tobacco Research and Policy Studies, in Washington, D.C. “But we can do it with anyone, anytime. It makes all those limitations worthwhile.”

The phone is always in your pocket, so whenever the thought emerges that maybe it’s time to quit, you can connect to help immediately.

“The social media piece in the [smoking cigarettes] cessation environment is very new,” says Rosamaria Amoros, a media and communications consultant with the state’s tobacco-control program. “Folks are experimenting, and we’re sharing, and we’re learning from each other.”

Amoros conceived and wrote Rhode Island’s antismoking cigarettes text messaging effort when asked to create an advertising campaign with very little money. Last year, the state won $483,000 in federal stimulus money for cigarettes cessation. Only 30 percent of it was set aside for media. Amoros looked for ways to stretch the dollars, supplementing the usual television, radio and billboard advertising with mobile and social media.

The texting campaign, which started in March and will continue through February 2012, costs a mere $18,000. That’s half as much, Amoros says, as it would cost to run a 30-second ad on network television for three or four weeks (not including the cost of developing the ad).

In addition to the text messages, Amoros is taking an approach that no other state has tried: QR codes. These are patterns of squares that, when scanned with a smartphone, link to a website. (You have to download a free app to read the codes.)

The codes are displayed on bus-shelter ads, where people are likely to be standing around doing nothing, perhaps smoking cigarettes. Those who scan the code will immediately link to the mobile version of QuitNowRI.com, the Health Department’s website that provides a wealth of quit-smoking cigarettes resources.

The cost of the QR code effort? About $25.

Amoros doesn’t know for sure how many people have taken advantage of the QR code, but 80 have accessed the website from mobile phones, most likely through the code. That’s 8.2 percent of visitors to QuitNowRI.com.

As for the text messages, so far, 22 people have signed up. The messages come at lengthening intervals –– 8 hours, 48 hours, 7 days and so forth, with eight messages spanning 90 days. “They are constant reminders of the damage [from smoking cigarettes], but also how you can turn this around immediately,” Amoros says.

Each message provides either a link to the mobile version of QuitNowRI.com or to the state’s tobacco-cessation hotline: 1-800-Quit-Now.

Another feature in the campaign is a ring-tone of someone coughing hard, a hacking, smoker’s cough. It sounds awful — and it’s one of the most popular features in the campaign, with 101 downloads.

“Rhode Island is part of this whole network that are all ... looking at how to add a mobile component,” says R. Craig Lefebvre, a research professor at the University of South Florida who designs public health and social-change programs. “The key thing is, you always have your phone with you,” Lefebvre says. “You’re carrying around 24/7 cessation assistance.”

“These same kinds of ideas are being applied to obesity, losing weight, diabetes and asthma,” Lefebvre adds. “These new technologies empower people to try it again. The more often you try, the more successful you’re going to be.”

Does it work? With smoking cigarettes cessation, the research, so far, indicates that text-messaging may help people quit, but it’s not clear whether they stay off cigarettes for the long term, Lefebvre says.

Cobb, of the Schroeder Institute, says that many questions remain about the best way to motivate people with texts.

It’s easy to get people to sign up, he says, but how do you make sure they read the messages, that they’re interesting enough, and come at appropriate intervals? The institute is experimenting with variations of a text-message program, trying to find out what works best.

Meanwhile, for someone like Providence mom Kotrina Lockard, all she can do is keep reading the occasional words of wisdom on her phone’s screen — and hope someday she can snuff out her last cigarette.

KEY POINTSMobile health

Cell-phone technology offers new opportunities for people to improve their health. Here are some examples:

The Rhode Island Department of Health smoking cigarettes-cessation effort includes text-messaging (to sign up, text QuitNow to 75309), a coughing ring-tone, and QR codes that link to QuitNowRI.com

Miriam Hospital’s Weight Control and Diabetes Research Center, in Providence, provides participants with weight-loss programs via cell phone, including videos, food-tracking apps and live or automated feedback.

Southcoast Hospitals Group in New

Bedford, Mass., has an app to help patients track medications, keep up with hospital news and find a physician.

Note of the day: menthol cigarettes read here.