Update of New Daily Persistent Headache.

Various new triggers and different NDPH mimics have been reported. The association with both cephalic and extracephalic pathologies suggests that NDPH is rather a syndrome with more than one disease mechanism. Recent clinical studies confirmed that migrainous headache remained the most prominent phenotype of NDPH, echoing the change of the diagnostic criteria in 2013. Diagnostic workup, including imaging studies, was unremarkable, except serving to exclude secondary etiologies. Studies on treatment options have yet shown promising targets, and randomized clinical trials are still lacking. Multiple mechanisms, both cranial and systemic, may be involved synergically in the generation of NDPH-like headaches. The search for effective treatment options should base on better understanding of disease mechanisms.