Why are Brolene Eye Drops (propamidine isetionate) used with caution in patients with dry eyes or a compromised cornea?

Brolene Eye Drops (propamidine isetionate) require caution in patients with dry eyes or a compromised cornea because benzalkonium chloride may cause eye irritation and dry-eye symptoms and affect the tear film and corneal surface; patients should be monitored during prolonged use.