As per the American Psychiatric Association (APA), the term drug dependence is described as a situation when a person needs one or more drugs just to function and with its withdrawal leading to physical disturbance. The most common difference between drug abuse and drug dependence is that abuse is usually considered as the initial phase of drug use that will lead to dependence in the future, if not treated. Drug dependence is a more severe problem than drug abuse. Worldwide, over 7 million people are a victim to using illicit drugs and this has caused many deaths. However, there are many mental effects of drug dependence before it becomes fatal.

Severe Depression

While depression can start the use of illicit drugs, drug dependence can further deteriorate the condition. In this case, the patient is caught in a vicious cycle of helplessness and hopelessness. Patients slowly lose their interest in daily activities, including taking basic care of them. This can further lead to changes in appetite, sleep disorder, sudden weight loss, fatigue, and physical pain.