What is the common cold of psychological disorders?

Answer: Adjustment Disorder.

Adjustment Disorder is a common short-term mental health disorder that develops in response to a specific stressful life event or change in circumstances. It is characterized by a range of symptoms, including feeling sad or depressed, difficulty concentrating, changes in sleep or appetite, and restlessness or irritability. Adjustment Disorder is often considered the "common cold" of psychological disorders because it is relatively common and can affect people of all ages, genders, and backgrounds. It typically lasts for a few weeks or months and usually goes away on its own. However, if symptoms are severe or persist for a long time, it is important to seek professional help.