ABSTRACT
Tear film dynamics can be affected by systemically administered pharmacological agents and locally applied adjuvants. Timolol applied topically reduces tear flow whereas pilocarpine stimulates tear flow. The adjuvant benzalkonium chloride disrupts the tear film whereas methylcellulose increases the stability of the tear film. Certain drugs can influence blink rate as well as tear secretion; for example, general anaesthetics may completely inhibit lid movements.
