Last year, doctors in the United States wrote more than four million prescriptions for nitroglycerin tablets, heart drugs placed under the tongue to stop a heart attack or reduce chest pain angina. The nitroglycerin will dissolve in the bloodstream, where it dilates the coronary artery and decreases blood pressure slightly, thus reducing heart exertion. When taken at the appropriate time, as chest pain just begins, the drugs can prevent a heart attack in three to four percent of patients. About eighty percent of these nitroglycerin drugs, however, have not been approved for sale, nor has the Food and Drug Administration (FDA) tested their safety and effectiveness. Doctors now fear their patients may have suffered unnecessarily as a result of this error. If patients took an ineffective nitroglycerin tablet, their chest pain could escalate to a heart attack. Pfizer’s nitroglycerin pill, Nitrostat, is the only nitroglycerin pill currently approved by the FDA.
The unapproved drugs claimed to be “grandfathered” in under the FDA’s policy that those drugs made before 1938 would not be reviewed. In recent years, however, the FDA has cracked down on a decades-old backlog of unapproved drugs. They sent warning letters last week to two drug manufacturers, Konec Inc. and Glenmark Generics, ordering them to stop producing these unapproved nitroglycerin tablets; they were given 90 days to stop manufacturing the drugs, and 180 days to stop shipping them. Until the order takes effect, however, the drugs are still being sold at pharmacies. While the drug makers insist their products are safe, they have agreed to comply with the order. The FDA said it has yet to examine the quality of the products they ordered off the market, but it has recorded problems with unapproved nitroglycerin products in the past.
Because the FDA has not officially recalled the products, some major pharmacy companies, such as Walgreens, says they will continue to make the product available. The FDA asks all patients taking the unapproved nitroglycerin product to continue taking their tablets, but to also consult with their physician regarding replacement prescriptions.