NHS Ayrshire & Arran, one of 14 health regions across Scotland, has a responsibilty to provide health and social care to almost 400,000 people.
But GMB Scotland said some of the region’s 8,000 staff were increasingly stressed at work and requiring sick days to recover.
The union used a Freedom of Information (FOI) request to uncover the amount of working hours lost by NHS Ayrshire & Arran through issues such as work related stress, anxiety and depression - a total of 198,162 hours between January 1 and December 31, 2016.
“These figures seem extraordinarily high but mirrors exactly what our members have been telling us for some time now,” said Paul Arkison of GMB Scotland.
“Due to staff shortages and extra demands that are being placed on them, many hard working hospital staff are struggling to cope and sadly for many of them they need to take time off to recover.
“This is leaving the remaining staff struggling to provide a service with limited resources.”
“It is imperative that NHS bosses start looking at why so many people are going off unwell, and if it is to do with workplace stress, then measures have to be put in place to ensure that the causes are being dealt with, rather than hard working staff returning to work to find themselves exactly in the same position.”
Patricia Leiser, human resources director at NHS Ayrshire & Arran, said like most employers in both the public and private sector, mental health-related issues accounted for the top reason for staff absence.
“We record absence using the standard 24 categories set by NHS Scotland, one of which relates to any health issue relating to mental ill health,” she added.
“Everything from a clinical mental health diagnosis to low mood following bereavement is listed under this category as well as stress, anxiety and depression.
“During 2016, 1.16 per cent of contracted hours were lost due to staff being absent for a mental health-related reason.”