Even Greener Pastures

In English you can also have a frog in your throat [be hoarse], a flea in your ear [having been sternly rebuked] or a monkey on your back [be addicted to something].

Ditto for the frog: einen Frosch im Hals haben

The one about the flea is a brilliant false friend, though. In German, jemandem einen Floh ins Ohr setzen means to make a suggestion to someone they are then unable to stop thinking about.

Oh, and does anybody else get einen Ohrwurm (earwig/earworm)? It's a catchy tune, seen as worming its way into your ear.