Sickness benefits is intended to support persons with a connection to the labour market who are unable to work due to their own illness. The rules on sickness benefits are regulates in the sickness benefit act (sygedagpengeloven).
It is a short-term benefit. In principle, you can receive sickness benefit for up to 22 weeks within the last 9 full calendar months. Before the end of the period of 22 weeks, the municipality will revaluate your right to sickness benefits. If you meet certain criteria, you may be entitled to an extended period of sickness benefits.