ELI5: Explain Like I'm 5

Adverse drug reaction

Okay kiddo, you know how when you take medicine, it's supposed to make you feel better, right? But sometimes, medicine can actually make you feel worse. That's called an adverse drug reaction.

Sometimes, when you take medicine, your body might not react well to it. It might make you feel sick, give you a rash, or even cause you to go to the hospital. Doctors and scientists study medicine for a long time before they give it to people, but everyone's body is different, and so sometimes medicine can have bad effects on some people.

So, if you ever take medicine and you start feeling really bad, like your tummy hurts, your head is spinning, or your skin is itchy and red, make sure to tell a grownup right away! They'll know what to do to help you feel better again.