The Effect of Ganglion Sphenopalatine Block Versus Placebo on Persistent Headache Following COVID-19 Infection
The Effect of Ganglion Sphenopalatine Block Versus Placebo on Persistent Headache Following COVID-19 Infection
The purpose of this study is to evaluate the effect of the ganglion sphenopalatine block (SPG
 block) on persistent headache following acute COVID-19 infection.
Adult patients with persistent headache following COVID-19 infection will be enrolled in the
 study. The patients will be randomised into three groups; bilateral SPG-block withto receive
 local anesthetic (lidocaine + ropivacaine), bilateral SPG-block with placebo (isotone NaCl)
 or bilateral "sham"-block with placebo (isotone NaCl).

 Primary outcome is hyperactivity in the sphenopalatine ganglion assessed by pain intensity
 (0-100mm on a visual analogue scale, VAS) of the headache in standing position 30 minutes
 after block in the group Ropicavain-Lidocain and "sham".
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 moderate to severe headache (NRS >= 3) 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.

 Exclusion Criteria:

 -  Patients who cannot cooperate to the study

 -  Patients who does not understand or speak Danish

 -  Allergy to the drugs used in the study

 -  Has taken opioids within 12 hours prior to intervention

 -  History of migraine or persistent headache before COVID-19 infection.

 -  Active COVID-19 infection (defined by the Danish Goverment regulations, i.e. 48 hours
 after last symptoms (omitting long term effects) or 7 days after positive COVID-19
 test if no symptoms.