Did you ever wonder how terrible it would be if you used that expired medicine in your medicine cabinet? In brief: far far less bad than you might think! Here’s an article from the Mayo Clinic about the US military Shelf Life Extension Program (SLEP). Nearly every drug tested out of the 122 drugs they tested maintained full potency 2-8 years after their expiration date. The only ones on their list that lost potency was Albuterol and Diphenhydramine (Benadryl). If you store your medicines in less than ideal conditions, your mileage may vary. Read it for yourself. Especially look at the tables.