For the parents of today’s “Generation Y” — and the guidance counselors and psychiatrists who meet with these teens — drug abuse and sexual promiscuity are still hot-button topics, risky behaviors that have bedeviled adolescents forever, or so it seems. But new threats are on the rise, and one in particular has caught many off guard: text messaging addiction.

In just three years, there has been a 600-fold increase in the number of text messages, with almost 5 billion sent every day in 2009 in the U.S., according to the CTIA — The Wireless Association. And many Americans believe that texting is a good thing, a way to stay in touch with friends and family. But is the growing dependency on texting in daily life becoming an addiction akin to alcohol or drugs?

Apparently so. Receiving a text message has been shown to light up the same area of the brain stimulated by highly addictive drugs such as heroin or cocaine. Similarly, some users have described feeling withdrawal and depression when denied access to texting; compulsive texters admit to feeling bad, anxious or sad when they do notget a message. Furthermore, teenagers are losing sleep thinking about their mobile devices. Researchers at the JFK Medical Center in Atlantis, Fla., recently found that one in five teenagers interruptshis or her sleep to text message, whilesome inexplicably even text while sleeping.

The addiction is not just physical, but social: Today’s teenagers cannot function among friends without it. Many of the 3,000 text messages sent on average per month by teenagers are used to plan parties and stay up-to-date with the latest gossip. Without texting, teenagers say, they fear becoming socially clueless.

But while texting may bond friends, it creates distance from family members — teenagers often ask their parents to text them instead of call — and texting conversations are often superficial. Sadly, many parents who were originally less familiar with texting are adopting the same habits as their children, rationalizing it as a “necessary evil” in order to be able to communicate with their kids.

The disruptions caused by text messaging are particularly visible in schools. According to the Association of American Educators, cell phones are one of the top three problems in terms of disciplining students. Teachers find that students who obsessively text often have falling grades, are lethargic and distracted in class, and cope poorly when the cell phones are confiscated.

And when this new risky behavior combines with old threats, the dangers of texting are even more evident. A shocking 28 percent of American teenagers admit to texting while driving, and this number is bound to rise even as states clamp down on the practice. Because adolescent brains are still developing — reaction and impulse controls not fully developed — they are even more prone to accidents when texting while driving. A 2009 study by the Virginia Tech Transportation Institute showed that drivers in general are 23 times more likely to be in a crash; the figures are surely higher for teenagers.

With text messaging technology always improving, we must be wary that constant improvement does not create increasing addiction to texting. Perhaps it is time to lay to rest the old saying that “idle hands are the devil’s playthings.”