Effect of timolol on aqueous humor protein concentration in humans

Short-term topical application of timolol, in a prospective, randomized, double-masked study of 32 human eyes, was associated with an average aqueous humor protein concentration of 38 mg/100 ml, compared to 13 mg/100 ml in control subjects (P less than .001). This apparent influence of timolol on aqueous protein levels probably resulted from reduced aqueous production. It did not affect the course of intraocular surgery.