[Wuli]

The same idea is usually true of a great many medicines.

The DOD and VA a number of years back took millions of doses of supposedly “expired” medicines in their stocks and put them through the most rigorous tests possible. Many were years past their expiration dates.

Most proved to contain as much active active-ingredients as supposedly unexpired medicines. The reason is because most medicines are not bilogically active; they are chemically inert and as long as they are stored in a dark dry place they usually are still good.

[outofsalt]

"Throw away any unused tetracycline (all cycline antibiotics) when it expires or when it is no longer needed. Do not take this medicine after the expiration date on the label has passed. Expired tetracycline can cause a dangerous syndrome resulting in damage to the kidneys." (Fanconi syndrome) https://www.drugs.com/tetracycline.html