to get the desired effect(s) or side effects, you would have to take in a significant amount of something for a period of time. that said, don't worry too much. popping 20 milligrams of oral steroid probably wont do much. im not sure about the "normal" dose coz im not so sure its legal either

oral steroids are usually taken in to treat some types of allergies, not for bulking up. try whey protein instead if you plan to bulk up.