inclusion criteria: - age > 18 years - moderate to severe headache (nrs >= 3) with self reported duration of minimum 6 hours during the past week as well as light to moderate headache (nrs >= 1) on the day of intervention. - onset of headache during or maximum 4 weeks after pcr-verified covid-19 infection. - headache must have persisted for at least 4 weeks following covid-19 diagnosis.

inclusion criteria: - age > 18 years - moderate to severe headache (nrs >= 3) with self reported duration of minimum 6 hours during the past week as well as light to moderate headache (nrs >= 1) on the day of intervention. - onset of headache during or maximum 4 weeks after pcr-verified covid-19 infection. - headache must have persisted for at least 4 weeks following covid-19 diagnosis.