Over the last two years, two companies have found themselves in the sights of the US Food and Drug Administration (FDA) after the regulator warned them for violating federal advertising regulations by "liking" unapproved claims on the social networking website Facebook.

But while FDA's warnings have yet to set off a wider crackdown on pharmaceutical companies, recent changes to the social media platform Twitter have raised the possibility that similar attention might soon be focused there.

Background

To date, FDA has sent two Warning Letters to companies regarding the "like" issue on Facebook.

In February 2012, FDA sent a letter to supplement marketer AMARC Enterprises after FDA investigators found that the company had "liked" claims made by customers that AMARC's products had cured their cancer. As a dietary supplement, AMARC could not market its product for any specific disease claims without first having obtained approval from FDA as a drug product, which it did not do.

A second letter, sent by FDA in July 2014, warned another dietary supplement manufacturer, Zarbees, for "liking" at least six unapproved claims about its product on Facebook. Those claims indicated the company's product could treat insomnia, bronchitis, pneumonia, cold, congestion and provide relief from allergies, FDA said.

FDA said it considered the company's "likes" to be equivalent to endorsements or promotions.

The Case for Twitter Vigilance

But while FDA has issued 11 Warning Letters regarding the improper use of Twitter to promote products, none have mentioned the use of a Twitter feature similar to Facebook's "Like" button: The "Favorite."

The star-shaped button has been around for years, offering Twitter users the ability to mark a post as a "favorite" of theirs, or simply offering users the ability to notify a poster that they have seen a tweet. But while the feature is old, within the last few months Twitter has rolled out a new aesthetic design that allows users to see what their friends are "favoriting" more easily than ever.

By clicking over to a Twitter user's homepage, you can immediately see all of their "favorite" posts simply by clicking on the "Favorites" tab of their profile.

In the case of FDA's main account, @US_FDA, there are just nine favorite tweets, including one praising FDA Commissioner Margaret Hamburg's (admittedly impressive) ability to ride a unicycle.

But while this feature may be mostly amusing for government agencies, it could potentially have pitfalls for companies that liberally use the "favorite" button to acknowledge posts. If FDA can chide a company for "liking" a post—something which requires a thorough review of every Facebook post—it can surely do so for "favoriting" a post as well, and even more easily now thanks to the change in which favorite tweets are prominently displayed on a user's profile.

For larger companies, this risk may not amount to much. GSK, for example, only appears to have "favorited" two tweets in its entire account history. Conversely, Merck has favorited more than a hundred posts, but appears to have done so carefully so as to avoid any mention of its products. Boehringer Ingelheim has hundreds of favorite tweets, and like GSK and Merck it appears to fastidiously avoid any mention of its products.

In other words, large, multinational pharmaceutical companies may already have strict social media policies in place that could help them avoid the sort of negative attention that could make its way into a Warning Letter. However, accidents can still happen, such as accidentally "favoriting" a tweet while using a mobile device.

Risk for Smaller Companies

But smaller companies, including those already cited by FDA for improper Facebook "likes" may be more at risk. For example, a review of Zarbees' Twitter account finds more than 500 favorited tweets, including ones that its product is effective at treating coughs—the same claim that FDA accused the company of improperly "liking" on Facebook.

While FDA called out the company's own tweets and retweets in its Warning Letter, it made no mention of its "favorites." It's not clear that the company had adopted the "new" Twitter profile appearance at the time of FDA's inspection of its website, which might have affected what the agency was able to find. Twitter only began rolling out those profiles in April 2014, and only made them mandatory on 28 May 2014. FDA's inspection was in May 2014.

Other companies, which either lack established social media policies or a deep familiarity with FDA's advertising regulations, could similarly be at risk.

And with many companies now maintaining a presence on multiple social networking channels, and the new ease with which consumers—and regulators—can read up on what someone has favorited, this could be one area FDA will soon be watching, if it isn't already.