Federal regulators have sent a letter to Abbott Laboratories (ABT) warning the company that promotional material for the anti-epilepsy drug Depakote is misleading because it omits important risk information.

Flashcards for Abbott's Depakote are misleading because they suggest the drug is safer than demonstrated, according to a letter the U.S. Food and Drug Administration sent on Jan. 22 to Illinois-based Abbott. The letter was posted on the FDA's Web site Thursday evening.

The FDA wants Abbott to remove the flashcards from the public and describe to the agency by Feb. 6 how it plans to do so.

Abbott has removed the flashcards, which were distributed to health-care providers, from circulation and plans to respond to the FDA by Feb. 6, said company spokeswoman Raquel Powers.

Depakote, approved in 1983, is used to treat manic episodes in people with bipolar disorder, and for patients with seizures. The drug's label has been changed more than six times to include, among other things, updated information about safety risks associated with the product.

The FDA said the flashcard doesn't include any risk information on the body. The agency said a statement on the front of the flashcard that refers people to important warnings on the reverse side is in small type and doesn't "mitigate this misleading presentation."

The Depakote warning letter comes about a month after Abbott received a warning letter for an advertisement for its psoriasis drug Humira. In December, the agency said an ad for Humira is misleading and makes claims not supported by scientific evidence.

-By Jared A. Favole, Dow Jones Newswires; 202.862.9207; jared.favole@dowjones.com

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