Ex-rad is a medicine that helps protect your body from harmful radiation. Radiation is a type of energy that can be really bad for your body if you are exposed to too much of it.
Have you ever heard of the sun giving you a sunburn? That's because the sun gives off a type of radiation called UV radiation that can damage your skin. But there are also other types of radiation like X-rays or gamma rays that can be even more dangerous.
Ex-rad helps protect your body from these harmful types of radiation by making special molecules inside your body that can fight against them. These molecules are like little shields that can block the radiation from hurting your body.
So, if you ever need your body to be protected from radiation, doctors might give you ex-rad to help keep you safe. It's like wearing a shield so the bad radiation doesn't hurt you!