Nasal vasoconstrictors delay onset. May be antagonized by concomitant (within 30 minutes) sumatriptan nasal spray. Sedation, dizziness, nasal congestion, insomnia, GI upset, respiratory depression ...

Interactions between beta-blockers like metoprolol and topical phenylephrine (a vasoconstrictor in Preparation H ... of ...

In these tissues, sumatriptan activates this receptor to cause vasoconstriction ... half-life of sumatriptan administered as a nasal spray is approximately 2 hours, similar to the half-life ...