It is a nervouse disorder, usually related to stress physical or mental, e.g. burnout, too much overwork, sleep deprivation, etc., resulting in symptoms like depression, anxiety etc.

As far as pills go, antidepressiva (e.g. Citalopram, Sertraline etc.) , antipsychotics (schizophrenia) or anxiolytics ( for anxiety-related disorders) can be prescribed.

Alternatively, or in combination, Cognitive Behavioral Therapy can be suggested. In some instances, Psychotherapy or even Hypnotherapy can be useful but it depends on the diagnosis and the severity of the mental imbalance

Causes of anxiety and depression are just as far ranging. from bad mental habits to physical or emotional abuse to chemical imbalances, disease, drugs or life situations and so treatment must focus on these as well.