When my unopened medication is about to expire, I take it to our local pantry before buying more. I only dispose of opened products. Last time I bought four bottles of povidone-iodine, consistent with my practice to avoid running out of a product. However, at least with povidone-iodine, anything more than one bottle is too much.

Edit: Does Gold Bond powder have an expiration date? I have been using it inside my shoes.

Jeanette Isabelle