The House of Representatives approved a move Thursday night that could smooth the way to over-the-counter use of emergency contraceptives like Plan B. Lawmakers unanimously passed a measure barring the FDA from keeping any contraceptive off the over-the-counter market once the agency has found it to be safe and effective. While the bill does not specifically mention the controversial emergency contraceptive known as Plan B, supporters were quick to point to the product as their motivation for pushing the vote. In May, an FDA advisory committee voted 23-4 to recommend that the FDA make Plan B available in drug stores without a prescription. In an unusual move, the FDA denied the recommendation, saying that Plan B maker Barr Laboratories Inc. hadn’t done enough to prove that Plan B was safe for girls under 16 years of age. The agency told Barr to either provide proof that Plan B was safe for adolescent girls or come up with a way to prevent them from buying it without a prescription.