Should have tried the Power of Rock.
Literally: medicine – stone – nothing – efficacy
Alternately: Neither medicine nor treatment were effective. The 石 in 薬石 refers to traditional Chinese treatments making use of stones, such as bian stones.
Notes: Some variation of this phrase may be used to describe a patient’s death from disease, although it seems to also be usable on a more metaphorical level.
Some people may replace 効 with homophone 功 (“achievement”), but 効 is preferred.