When Kim Kardashian speaks, the FDA listens.

Or, more precisely, when Kardashian, who has 46.8 million followers on Instagram, posts an enthusiastic endorsement—and advertisement—on the social media platform for Diclegis, a prescription drug for treating morning sickness, the agency takes notice (and gives it). In a letter to Duchesnay Inc., the drug’s makers, the FDA reprimanded the company for the “false or misleading” post and requested not only that Duchesnay take down the post, but that it submit a “comprehensive plan of action to disseminate truthful, non-leading, and complete corrective messages” about the drug.

Kardashian’s post, which has since been taken down, included the following comment next to a picture of her holding a bottle of Diclegis:

“OMG. Have you heard about this? As you guys know my #morningsickness has been pretty bad. I tried changing things about my lifestyle, like my diet, but nothing helped, so I talked to my doctor. He prescribed me #Diclegis, and I felt a lot better and most importantly, it’s been studied and there was no increased risk to the baby. I’m so excited and happy with my results that I’m partnering with Duchesnay USA to raise awareness about treating morning sickness. If you have morning sickness, be safe and sure to ask your doctor about the pill with the pregnant woman on it and find out more www.diclegis.com; www.DiclegisImportantSafetyInfo.com.”

While the post may not have caught the FDA’s attention if it were merely a personal story from a relieved mother-to-be, the fact that Kardashian’s post constituted a paid advertisement subjected it to FDA scrutiny. As the FDA wrote in its letter to Duchesnay, “Promotional materials are misleading if they fail to reveal facts that are material in light of the representations made by the materials or with respect to consequences that may result from the use of the drug as recommended or suggested by the material.”

In other words, promotional material must fully communicate the risks of a drug as well as its benefits. It was not enough that Kardashian’s post referred to the Diclegis website for risk information; this reference “does not mitigate the misleading omission of risk information.”

In addition to its failure to fully communicate the risks of Diceglis, the FDA also cited Kardashian’s post for failing to provide material information of any important limitations to use. In this case, the FDA points to Diceglis’ FDA-approved product label, which states that the drug has not been studied in women with a severe form of morning sickness.

The FDA’s reference to Diclegis’ FDA-approved product label may suggest that, to avoid controversy and ensure compliance with FDA regulations, promotional material disseminated through social media should include a substantial amount, if not all, of the information required on the product label. Under federal regulation, a prescription drug label must include, among other information, limitations statement, date of initial approval, recent major changes, indications and usage, warnings and precautions, adverse reactions, drug interactions, and use in specific populations. In fact, after receiving the FDA’s letter, Duchesnay formulated a #CorrectiveAd that Kardashian posted on Instagram, which included a paragraph of narrative, listing lengthy detail about risks and limitations of the drug.

It will be interesting to see how the FDA continues to regulate drug and medical device promotion on social media platforms in light of the unique nature and appeal of social media to companies and consumers alike. (Current FDA draft regulations on advertising on social media platforms can be found here.) Requiring promotional materials on social media platforms to provide the risk and limitation information found on a label or website is arguably at odds with the spontaneous, personal, and brief nature of social media platforms like Instagram, Twitter or Snapchat. While Instagram may allow narratives of up to 2,200 characters, Twitter’s 140-character limit does not provide easy compliance with the FDA’s recent directive to Kardashian. And a twelve-part Twitter ad for a prescription drug just does not have the same appeal. The FDA’s regulations, which already seem out of step with the brevity of expression common on social media, are likely to continue to clash with ever-evolving technological platforms.