Answer:
Overdose, dependency
Step-by-step explanation:
Overuse of drugs can become an overdose and can be lethal. Even prescription drugs can cause overdose if enough is used. It is extremely dangerous to take more than the recommended amount of prescribed medicines.
When people use a certain drug to remove pain or feel happier in a way, the become dependent on the drug. This makes them addicted, and if they try to remove the drug from the equation they become sick because they were so dependent on the specific drug.