As I understand it, many people do not follow the doctor's instructions for taking medicine which makes this an interesting topic. Here are some other ways to word this:
1. How important is it for doctor's to give careful instructions for taking medicine?
2. Should doctors do more to make sure patients correctly take medicine?
3. Why should we follow the doctor's orders when taking prescription medicine?
4. How can we better make people aware of the importance of taking medicines as prescribed?
5. When do you need to be sure to finish all of the medicine a doctor gives you?