Doctors in the United States wrote more than four million prescriptions for nitroglycerin tablets last year. Commonly referred to as nitro, these under-the-tongue pills are used to relieve chest pain associated with heart disease (angina) or to stop a heart attack (myocardial infarction).
However, the doctors who prescribed these drugs and the patients who took them have just learned that about 80% of the drugs dispensed had not been approved by the Food and Drug Administration (FDA).
Worse still doctors have no way of knowing whether patients may have suffered unnecessarily as a result.
“If it’s not approved and no one has tested it, we can’t be sure that it’s safe and effective,” warned Dr. Harry M. Lever, a cardiologist at the Cleveland Clinic.
The FDA sent warning letters in late March to suppliers of the unapproved tablets giving them 90 days to stop making the drugs and 180 days to stop shipping them.
The FDA said that it had not examined the quality of the products it was ordering off the market but that it had recorded problems with other unapproved nitroglycerin products in the past. The agency advised people who take unapproved nitroglycerin to continue taking their tablets but to consult their doctors about replacement prescriptions.
Only one brand of nitroglycerin pills is FDA approved: Pfizer’s Nitrostat. Pfizer says it has stepped up production of the drug and expects to be able to meet the entire US market demand.