Could you have low testosterone?

That's the question Abbott Laboratories (now AbbVie) has been urging men to consider with its "Is It Low T?" awareness campaign, a highly effective effort to change how doctors and the public think about managing aging in men.

Since 2008, this massive marketing endeavor has targeted middle-age men who have put on some weight, sometimes feel grumpy or get sleepy after meals, encouraging them to have their testosterone levels tested and to consider treatment if levels are low. It has helped persuade legions of men to take a drug that may not help and may actually do harm for a condition they probably don't have.

Since the start of the campaign, testosterone sales, which had been stable for years, have risen more than 1,800 percent, exceeding $1.9 billion in 2012.

But there's a big problem: We really don't know if diagnosing and treating "low T" does any good. More important, there is some evidence it may cause harm. Last month, a new study of men found that older men taking the drug were more likely to have heart attacks. Soon after the study's release, the Food and Drug Administration announced a new investigation into the possible harms of testosterone.

Testosterone drugs were initially developed for a narrow use: treating men with a reduced ability to produce testosterone because of such things as trauma, chemotherapy, genetic abnormalities or undescended testicles. For these men, testosterone replacement provides a clear quality-of-life benefit, permitting normal sexual development or restoring male appearance and sexual function.

But drug information approved by the FDA is ambiguous about which conditions testosterone drugs are approved to treat. This matters because pharmaceutical companies can promote drugs only for "on-label" FDA-approved uses. Years ago, the Institute of Medicine, the nation's premier medical advisory group, described prescribing testosterone for low T as an off-label use. Last month, the FDA seemed to agree. In announcing its new investigation, the agency specifically mentioned that testosterone is approved only to treat hormonal problems caused by medical problems. So why has the FDA tolerated six years of aggressive marketing of the drug to a much wider range of potential patients?

One reason is that the FDA only regulates advertisements that mention drugs by name. Strictly speaking, the disease awareness campaign does not mention any brand names. But this seems like sophistry since the "Is It Low T?" website links to a direct-to-consumer website for the testosterone gel Androgel. Doesn't this bump up against FDA regulations about off-label promotion?

It's time for the FDA to rein in these kinds of "disease awareness" campaigns and branded advertising, because they are misleading: They imply unproven benefits and ignore possible harms.

The proven benefits of treating low T are small: subtle increases in lean body mass, libido or sexual satisfaction. Studies have found no improvement or inconsistent results when it comes to effects on weight, depression or strength; effects on energy and irritability are unknown.

Moreover, any benefits need to be weighed against the possibility of serious harm. A randomized trial published in the New England Journal of Medicine in 2010 raised concerns about giving the drug to frail, elderly men. The trial was stopped early because 7 percent of the men in the testosterone gel group versus 1 percent in the placebo group experienced serious heart problems.

For men with severe hormone deficiency from a medical problem, testosterone replacement is a major advance. But for the aging men targeted by the low T campaign, the balance of benefits and harms is unknown. And there is good reason to worry about heart attacks, especially in men with heart disease and in the frail and elderly.

When it comes to testosterone, the pharmaceutical industry has gone too far - and the FDA not far enough. Maybe the problem isn't low T; maybe instead it is low R - low regulation.

Dr. Steven Woloshin and Dr. Lisa M. Schwartz are internists and professors of medicine at the Dartmouth Institute for Health Policy and Clinical Practice. They wrote this for the Los Angeles Times.