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Calcitonin gene-related peptide (CGRP) has emerged as a key player in migraine pathophysiology. It led to the development of specific antimigraine therapies (anti-CGRP monoclonal antibodies (anti-CGRP mAbs)), but challenges remain in its use as a biomarker. Evidence showed elevated plasma CGRP levels in migraine patients compared with controls and in the ictal phase compared with the interictal phase, and that plasma CGRP levels could help predict the response to anti-CGRP mAbs.1 However, CGRP in plasma is difficult to evaluate due to its low concentrations and short half-life. Therefore, alternative routes for analysing CGRP concentrations, mainly tears and saliva, are obtaining increasing interest, particularly reflecting the proximity within the trigeminal nerve branches.2 To date, no studies have analysed CGRP levels in tear fluid using the Schirmer test for tear collection, which is a completely non-invasive method. Because trigeminal fibres densely innervate the eye,3 this study aimed to compare CGRP in tear fluid of migraine patients and healthy controls (HCs) and to evaluate if anti-CGRP mAbs can modulate the CGRP concentrations in migraine patients.