Subsensitivity to pilocarpine of the aqueous outflow system in monkey eyes after topical anticholinesterase treatment.

Cynomolgus and vervet monkeys were treated unilaterally with topical echothiophate iodide twice daily for eight to 25 weeks. The effect of intracameral pilocarpine on outflow facility was determined in the ganglionic-blocked animal during and after echothiophate treatment. The echothiophate-treated eyes demonstrated marked subsensitivity to pilocarpine, and required several weeks to months to recover normal pilocarpine sensitivity.