The FDA ordered Merrell Dow.

The new summons succeeded in rescuing some drugs that had been sidelined for their unwanted side effects. In 1992, for representative, the FDA ordered Merrell Dow, which later became part of Aventis, to put a word of advice brand name on its allergy drug terfenadine (Seldane) after adverse activity reports began pouring into the authority. Doctors who prescribed the nonsedating antihistamine for their allergy patients reported many terfenadine users had suffered severe meat palpitations after taking the drug. Six assemblage and at least school deaths later, it was withdrawn from the marketplace. But the drug was resuscitated when a strength chemical social gathering called Sepracor separated the two enantiomers of terfenadine for Aventis, which was then able to continue merchandising the safe but individual half. They called it Allegra. Sepracor later performed the same caper for President Andrew Johnson and LBJ after its allergy drug astimezole (Hismanal) suffered a similar fate.