Cardiovascular and intraocular pressure effects and plasma concentrations of apraclonidine

Arch Ophthalmol. 1990 Sep;108(9):1264-7. doi: 10.1001/archopht.1990.01070110080029.


We performed a double-masked, crossover study comparing the cardiovascular and intraocular pressure effects of 0.5% and 0.25% topical apraclonidine hydrochloride and 0.5% timolol maleate in 20 healthy female volunteers. The contralateral effects of unilateral apraclonidine and the plasma concentrations of apraclonidine were also assessed. All measurements were done 2, 5, and 8 hours after drop instillation. A 15-minute treadmill test was performed after the 2-hour measurements. All three active medications lowered intraocular pressure comparably. There was no significant contralateral intraocular pressure effect seen with apraclonidine. The apraclonidine plasma concentrations were variable and unrelated to the amount of intraocular pressure lowering and cardiovascular parameters measured. Apraclonidine did not affect blood pressure or heart rate any differently than placebo. Timolol, however, blunted exercise-induced tachycardia. There were no significant differences in pupillary diameters or interpalpebral fissure widths among treatment groups.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Administration, Topical
  • Adult
  • Analysis of Variance
  • Blood Pressure / drug effects
  • Cardiovascular System / drug effects*
  • Chi-Square Distribution
  • Clonidine / administration & dosage
  • Clonidine / analogs & derivatives*
  • Clonidine / blood
  • Clonidine / pharmacology
  • Double-Blind Method
  • Exercise Test
  • Female
  • Heart Rate / drug effects
  • Humans
  • Intraocular Pressure / drug effects*
  • Middle Aged
  • Randomized Controlled Trials as Topic


  • apraclonidine
  • Clonidine