A doctor you follow on Twitter swears by a certain drug for boosting female libido. Another touts a cholesterol medication on Facebook, exclaiming how well it works.

What these social media posts don’t tell you, aside from these drugs’ possible side effects, is that the doctors may be getting paid a pretty penny by the pharmaceutical industry for their public enthusiasm.

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In an investigation by STAT, the health news publication produced by Boston Globe Media, reporters looked at hundreds of social media accounts of health care professionals. They found these experts “virtually never note their conflicts of interest,” which can include payments of tens or even hundreds of thousands of dollar from drug companies, according to STAT.

It’s not just drugs doctors are being paid to promote. Some promote medical devices, such as ones used in robotic surgeries.

While physicians are typically expected to disclose financial conflicts of interest when they publish a paper in a medical journal, no such standards apply online — so far.

According to a 2015 Business Insider report, type 2 diabetes drugs and anti-clotting medications (aka blood thinners) were among the types of drugs pharmaceutical companies paid the most to have doctors promote.

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STAT reports some medical societies are working to put rules in place to govern their members' social media behavior. Massachusetts Medical Society’s social media guidelines now state that “Physicians must disclose all relationships they have with regard to the maker or provider of products and services they review or discuss in online communities. This includes discussions and reviews of products and services provided to the physician for free.”

You can search particular doctors to see how much drug company money they received between August 2013 to December 2014, the latest year for which complete data is available, courtesy of ProPublica, an independent, non-profit newsroom that produces investigative journalism in the public interest.

It seems consumers can’t get away from drug promotions no matter where they look. The New York Times recently wrote about drugs ads on TV, noting the rise in advertisements for expensive, niche drugs in particular. According to the American Medical Association (AMA), the United States and New Zealand are the only two countries in the world that allow direct-to-consumer advertising of prescription drugs.

The AMA has called for a ban on TV ads for drugs and medical devices. Not only do marketing costs drive up drug prices, the group notes, “Direct-to-consumer advertising also inflates demand for new and more expensive drugs, even when these drugs may not be appropriate,” said AMA Board Chair-elect Patrice A. Harris, MD.

No matter where you see a drug advertised or promoted or by whom, before taking any new prescription, health experts recommend you ask your doctor these questions among others: why you need the drug, what the potential side effects are and whether there’s an older drug or a lower-cost generic that might work just as well.

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Marianne has been producing content that informs and inspires for more than 20 years, with a deep focus on bringing readers accurate, actionable advice and helping them live healthier, safer lives. Before launching SafeBee, she was executive editor of Sharecare, the health website and social network. Previously, she developed more than two dozen illustrated consumer health books for Reader’s Digest. Her writing has appeared in numerous outlets including Arthritis Today and WebMD. Her favorite safety tip: Know the purpose of every medication you take and under what circumstances you can stop taking it.