A team of medical researchers affiliated with several institutions in the U.S. has found that a high percentage of doctors posting endorsements regarding drugs on the social media site X were paid to do so by the makers of the drugs.

In their study, published in JAMA, the group searched for drug endorsements by doctors on X and then used a website called Open Payments to find out if they had been paid for their endorsements.

The United States is one of the few developed countries that allows pharmaceutical companies to advertise the drugs they make and sell, including via radio, television and social media sites. It is also legal in the US for doctors and other health care professionals to receive payment for endorsing the drugs featured in advertising.

In this new effort, the research team noted that the website Open Payments (run by the Centers for Medicare and Medicaid Services) allows interested parties to identify doctors practicing in the U.S. who have received money for endorsements and the name of the party that paid them. The team had questions about doctors making endorsements on social media sites.

To learn more, the researchers focused their efforts on X, formerly Twitter. They began their study by searching for doctors who were posting drug endorsements and found 28 of them. They searched the name of each doctor on the Open Payments website to learn more about their endorsement history. They found that 26 of the doctors on X had received payments from the manufacturer of the drugs they were endorsing. They also found that 24 had received payments related to the specific drug they were endorsing.

The researchers noted that most of the payments were made under the categories of "speaking" or "consulting," and that most of the postings were also sponsored testimonials. They also found that only one of the doctors was involved in research leading to the development of the drug being endorsed.

The research team points out that while some may see the practice of being paid to endorse drugs as unethical, it is not illegal and does not affect licensing.