A new study suggests it may also help dry eye.
The research team did a retrospective chart review of 76 patients who received Botox to treat their chronic migraine symptoms. Prior to the Botox treatment, the patients filled out several questionnaires gauging their level of photophobia and dryness.
What did they find?
After receiving Botox, there was a significant improvement in photophobia symptoms and also improvement in patients who had reported severe dry eye symptoms.
How are these things connected?
The trigeminal nerve pathway, specifically the calcitonin gene-related peptide (CGRP). This peptide has been a well-studied implicator in both migraines and photophobia. When Botox is injected, there is decreased signalling through the primary trigeminal afferents which may account for the improvement in symptoms. The other theory is that Botox may decrease the release of inflammatory mediators, such as CGRP.
The take home:
The migraine and dry eye correlation isn’t a new finding. There are several studies that show patients with migraines are more likely to report dry eye symptoms and photophobia. This study shows that using Botox to treat chronic migraines may also improve photophobia and dry eye symptoms. (via)