The FDA has ordered Glenmark Generics and Konec Inc. to stop marketing unapproved nitroglycerin tablets. The FDA’s warning letters require Glenmark and Konec to remove the unapproved tablets as part of the FDA’s Unapproved Drugs Initiative. The unapproved nitroglycerin tablets have not been proven safe and effective, and the FDA has not reviewed the quality and labeling of these products. The unapproved products may differ from approved nitroglycerin products in some respects, such as formulation and labeling. The FDA has seen significant quality and efficacy problems with unapproved nitroglycerin products.

Glenmark and Konec have 15 days to respond to the FDA with a plan for removing their products from the market. They have 90 days from the date of the warning letters to stop manufacturing new products and 180 days to stop further shipment of existing products. The FDA does not anticipate a supply problem for nitroglycerin tablets, which is available in an FDA-approved formulation from Pfizer as Nitrostat.

Nitroglycerin tablets are indicated for the acute relief of angina attack and for the prophylaxis of angina pectoris.

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