Stupid
You're sick because you put an arrow in your mouth and tried to eat it. To be honest, that's just really stupid. You have to be stupid to try to eat an arrow. You deserve to be sick.
ち
おろか, し
None
The only way to cure this serious case of stupid is to make you eat cheese (ち). Not only will it fix your sick stomach by cushioning all the arrows that you shoved in your stupid mouth, but it should send smart cheese waves to your brain and cure you of that stupid all together.