A study into workplace stress by researchers at Berlin University has identified a new ailment labelled post-traumatic embitterment disorder.
Workers can be affected if they are regularly passed over for promotion, feel undervalued by their employer or are humiliated in front of colleagues.
The report said, "There are many mental disorders which can result in workplace phobia, such as depression, paranoid disorders or personality disorders. One disorder of special importance is the post-traumatic embitterment disorder.
"This can be defined as a prolonged reaction to events of injustice or humiliation, which lead to feelings of embitterment, hopelessness, aggression, self-blame, or avoidance of trauma-related places and persons."
Symptoms include "taking sickies", feeling helpless, aggressive or down-hearted, having a poor appetite, nightmares and phobias about people or places linked to the job. In extreme cases, victims feel suicidal or quit their job never to return said Michael Linden, the professor who led the research team.
Some victims of office bullying began smiling broadly when asked to think of revenge against their workplace oppressors, the research team found.
Linden said, "These patients not only show phobic reactions when they are asked to go back to their work but also often actively reject help as an expression of embitterment."
People could be particularly vulnerable to the condition if their lives revolve around their work, he said.
Those employees who pay more attention to other areas of life, such as family or hobbies, are less likely to suffer, the study found.