When being unwell affects your ability to work, your employer may need a fit note as confirmation. Issued by a doctor or other healthcare professional, it outlines the nature of your absence and tells your workplace that you are unfit or fit - but may need reasonable adjustments - for work.
This is a companion discussion topic for the original article at https://patient.info/features/general-health/what-is-a-fit-note-and-when-do-you-need-one