What is the difference between using and abusing a drug?

Explanation:

If this is like an explanation with no "correct answer," here's my opinion.

Drugs can be used in resourceful ways to treat people from a certain disease or relieve pain but drugs can also be abused at times. An example of abusing drugs is buying and consuming illegal drugs without a prescription from a doctor or using drugs to harm others or even yourself. To conclude, the difference between using and abusing a drug is using a drug is usually for a good cause while abusing a drug is usually for a harmful or bad cause.