After a couple of days, it would have lost its potency.

The image, for the record, has not lost its potency.

The lines have not quite lost their ancient potency, either.

And of course there was always the chance that the batch had lost its potency.

What if her shield or whatever it was should lose potency?

But five years later, the drug lost its potency.

"Could the herb have lost its potency after it had been in the water awhile?"

Fortunately, the juice lost its potency after a few seconds.

The shadow, far from losing potency, had grown a little.

Even among people who routinely lived for over five hundred years, events lost their potency and relevance.