Drugs and alcohol use can either lead to and/ or result from depression. This is generally described as a co-occurring disorder where a primary substance use disorder can lead to an increase in depressive states depending, not the frequency and amount of substance abuse. Alternatively, a depressive episode can lead to an increase in drug or alcohol abuse in an effort to quell the painful mental symptoms associated with depressive states. Alternative if depression is a cyclical or season occurrence in your life and a significant substance use disorder formed away from the depressive cycle, this would amount to what is known as a dual diagnosis or multiple mental health disorders happening regardless of when and where the drug/ alcohol use arises in relation to the depressive state. Causes of depression in the dual diagnosis sense can be genetic and are often seen in families where multiple family members experience depression. However, just because other family members experience depression within the family system does not mean that you will automatically fall into the present or future depressive states. Personality traits such as a tendency to worry a lot, are perfectionist, have low-self-esteem, or those who are self-critical and often negative are generally at risk of developing depression by comparison to other subgroups of people. Serious medical illnesses that are chronic or life-threatening can also lead to depressive episodes. Life circumstances or other personal factors are likely influencers of depressive episodes. Depression is a complex disorder that cannot be simplified to a “chemical imbalance,” or whether you have to little or too much of a particular brain chemical. Factors include genetic vulnerability, severe life stressors, drug and alcohol use, or other medical conditions that can affect the way your brain regulates your moods. Most modern antidepressants have an effect on your brain’s chemical transmitters (serotonin and noradrenaline), which relay messages between brain cells – this is thought to be how medications work for more severe depression. Psychological treatment can also help you to regulate your moods. Effective treatment can stimulate the growth of new nerve cells in circuits that regulate your mood, which is thought to play a critical part in recovering from the most severe episodes of depression.