In 2009 alone, more than four million prescriptions were written for nitroglycerin tablets that had not been approved by the FDA, the agency has said, representing 80 percent of all prescriptions written.
Nitroglycerin tablets are commonly prescribed to patients at high risk of heart attacks. When a patient feels chest pain or another early sign of a heart attack, the tablets are dissolved under the tongue. They cause blood vessels to dilate, and can prevent or stop a heart attack in up to 4 percent of cases.
Because the tablets were in use before the passage of the Food, Drug and Cosmetic Act in 1938, manufacturers have always claimed they can continue selling them without FDA approval. Yet in recent years the FDA has begun cracking down on unapproved medications, disputing this interpretation of federal drug law.
“If it’s not approved and no one has tested it, we can’t be sure that it’s safe and effective,” said cardiologist Harry M. Lever of the Cleveland Clinic.
The FDA recently sent letters to two manufacturers of unapproved nitroglycerin tablets, Konec Inc. of Tucson, Ariz., and Glenmark Generics Inc. of Mahwah, N.J., giving them 90 days to stop manufacturing the pills and 180 days to stop distributing them. Drug stores have stated that they will continue to sell the products until they are no longer available.
“We still have the [Glenmark] product available,” said Walgreens spokesperson Robert Elfinger. “This is not a recall.”
The FDA said it had not received any reports of problems with Glenmark or Konec’s products, but that it had been notified of problems with other unapproved nitroglycerin tablets.
Upon hearing of the FDA action, however, Lever recalled an incident in which a heart surgery patient had brought back a bottle of Glenmark pills he had prescribed to her. The pills did not relieve her chest pain, she told him, or cause any of the side effects that her prior batch of pills had.
“Every day, when I’m writing a prescription,” Lever said, “I’m thinking, ‘Is the patient going to get the right stuff?'”