Self-medicating can appear harmless at first, but over time, it can result in dependence on your substance of choice. In addition, it has been associated with the exacerbation of symptoms for some mental illnesses, and it can predispose users to developing mental health issues in the future. If someone with a mental illness self-medicates, then that means they aren’t taking the time to develop healthy coping mechanisms. This can lead to their mental illness worsening and drive them to lean more and more on drugs and alcohol.