Remove package's dependencies (does not remove package):
brew deps [FORMULA] | xargs brew remove --ignore-dependencies
Remove package:
brew remove [FORMULA]
Reinstall missing libraries:
brew missing | cut -d: -f2 | sort | uniq | xargs brew install
Now, it may be easier to instead run:
$ brew uninstall [FORMULA] $ brew deps [FORMULA] | xargs -n1 brew uninstall
xargs -n1
will force xargs to only take one argument at a time, so you'll have the same number of calls to `brew uninstall as number of dependencies. Then you can rely on brew to decide whether a dependency isn't required anymore (so it'll uninstaall it) or if the dep is required by something else that brew call will fail and xargs will move on.