Headache in COVID-19 and Long COVID: to Know Facts for Clinical Practice.

Headache mechanisms in COVID-19 are still poorly understood. Strong evidence is also lacking on how to best treat and manage these patients, especially those with persistent and disabling headache after COVID-19. Data are also scarce on the characteristics of headache in COVID-19 caused by the new SARS-CoV-2 (Omicron) variants and how these may influence the acute and persistent symptoms of COVID-19. Patients with pre-existing primary headache disorders remain a particularly concerning population due to their biological predisposition in suffering from headaches and the potential risk of worsening in the setting of SARS-CoV-2 infection. Although there is an exponential growth of scientific evidence, studies are often controversial and focused on the first wave of the pandemic, making COVID-19 headache still a challenging matter for clinicians. New research is therefore needed.