UPDATED: Kim Kardashian Instagram post lands Duchesnay in FDA hot water

Kim Kardashian is promoting Duchesnay's morning sickness drug, Diclegis, on Instagram.

It isn't too often that a celebrity spokesperson for Big Pharma goes off the reservation. But in the case of celebutante Kim Kardashian and Canadian pharma Duchesnay, that's exactly what happened. The FDA is coming down on the celeb's social media post for the company's morning sickness med, Diclegis, saying it violates the agency's branding rules.

Duchesnay found out that Kardashian was taking the med to reduce symptoms during her second pregnancy, and tapped the reality TV star to promote the drug via social media. Last month, the celeb magazine cover girl took to Instagram to get the word out about Diclegis.

"OMG. Have you heard about this?" Kardashian wrote in a caption on Instagram. "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, I felt a lot better and most importantly, it's been studied and there was no increased risk to the baby."

Obviously, Kardashian didn't get much training in FDA fair-balance rules. No wonder the FDA's Office of Prescription Drug Promotion (OPDP) is none too pleased with the Kardashian endorsement, sending Duchesnay a letter calling the Instagram post "false and misleading." The post does not talk about any risks associated with the drug, the agency said in its note, even though it links to a Diclegis website with safety information at the end. And it doesn't provide information about Diclegis' full indication, which has not yet been studied in pregnant women with hyperemesis gravidarum, or prolonged vomiting.

For all those reasons, "the social media post misbrands Diclegis" under the Federal Food, Drug and Cosmetic Act (FD&C) and "makes its distribution violative," the FDA said in its letter. The agency is asking Duchesnay to stop misbranding the drug "immediately," submit a written response to its letter with a plan for discontinuing the ads and clearing up the issue. If Duchesnay doesn't comply with regulators' requests, the FDA could take additional action.

This is not the first time the FDA has cracked down on Duchesnay for questionable branding. In November 2013, the OPDP sent the company a note after it won approval for Diclegis. The drugmaker's approval announcement was "false or misleading" because it left out all risk information and facts regarding Diclegis' limitations, the agency said in its note. Now, regulators are worried that Duchesnay is headed down a similar path with its recent infraction.

And the FDA crackdown could throw a big wrench into Duchesnay's marketing for the drug. According to pharma marketing analytics firm Treato, since Kardashian became a spokeswoman for the brand, conversations about the drug have increased more than 500%. The day the celeb spoke out for Diclegis, online conversations about the med jumped more than 6 times from the day before.

The latest drama also comes as the FDA doubles down on pharma's social media branding. Last year, the agency released new social media guidance that would limit drugmakers' marketing through outlets such as Facebook ($FB) and Twitter ($TWTR), triggering backlash from industry groups that called the measures too restrictive.

And some lawmakers are pushing back. In June, a Missouri congressman introduced a bill that would force the FDA to let pharma share more information about its products online. The bill would allow drugmakers to use hyperlinks for risks and benefits, rather than spelling them all out in posts.

- here's the FDA letter

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Editor's Note: This story was updated with information about Duchesnay's Diclegis campaign.