Stress is a difficult issue for businesses to deal with and can be something of a catch-all for a range of medical and emotional issues. The key is consult with the employee suffering from stress to find out the extent of the problem and try to come up with a solution that suits both parties.
Stress can be extremely costly for businesses and as an employer you have a duty of care to assess and take measures to control risks from work-related stress.
Stress may be related to work itself – for example an excessive workload, bullying, lack of training, an INability to deal with the level of responsibility, or related to other issues outside of the workplace.
In both of the situations you as an employer may be able to assist the employee affected to find a mutually beneficial solution.