In 1979, a law was passed requiring drug manufacturers to stamp an expiration date on their products. According to the Harvard Medical School Family Health Guide, this is the date that manufacturers can guarantee full potency and safety of the drug. Over a decade ago, the Federal Drug Administration conducted a study and found that more than 90 percent of medications retained their effectiveness after the specified expiration date. It may be time to take a look inside your medicine cabinet and do some cleaning.
Tetracycline is an antibiotic prescribed to treat bacterial infections, acne, and urinary tract infections. It prevents the growth and spread of bacteria. Tetracycline should be taken only as directed Discard any medication that is not needed or expired. Taking expired tetracycline causes a serious kidney condition called Fanconi syndrome. According to Medline Plus, Fanconi syndrome is a disorder of the kidney tubes or ureters. Substances which are normally absorbed into the bloodstream by the kidneys are released into the urine instead.
According to an article by Martin M.Grajower, M.D., et al., on the online journal Diabetes Care, even though an expiration date is stamped on each bottle of insulin, loss of potency can occur after the bottle has been in use for less than or equal to one month. Diabetic patients are strongly advised not to use insulin past the expiration date stamped on the bottle.
Nitroglycerin is a medication prescribed to relieve or prevent an acute attack of angina. The effectiveness of nitroglycerin decreases as it gets old. It functions as a vasodilator by opening blood vessels to improve blood flow. This drug loses its potency after its specified expiration date. Patients with angina are strongly encouraged get a new prescription and to discard the expired medication
Warfarin is an anticoagulant prescribed as treatment to prevent clot formation. It is used as preventative treatment in cases of atrial fibrillation, following cardiac valve replacement, and to reduce the risk of strokes and heart attacks. Warfarin is a drug which loses its potency over time.