Drug abuse is defined as, compulsive, excessive, and self-damaging use of habit forming drugs or substances, leading to addiction or dependence, serious physiological injury (such as damage to kidneys, liver, heart) and/or psychological harm (such as dysfunctional behavior patterns, hallucinations, memory loss), or death. Also called substance abuse.

Drug addiction is a  severe, potentially life-threatening disease. People who suffer from addiction experience hardships like serious health problems, legal troubles, and loss of support from friends and loved ones. Every hardship an addict faces causes depression. Once an addict is depressed, they turn to self-medicating the only way they know how; abusing harmful substances. As a result, the user creates a sick cycle of abusing: they become depressed from the consequences of abuse, then use the cause of depression (drugs) to treat the depression it caused then.

In addition, those who suffer from the disease of addiction require clinical, psychiatric care. Therapeutic services such as rehabilitation centers, residential treatment facilities, and transitional living programs are viable options for an addict to utilize.