The cardiovascular, pulmonary, and ocular hypotensive effects of 0.2% brimonidine

Arch Ophthalmol. 1995 Jan;113(1):77-83. doi: 10.1001/archopht.1995.01100010079024.

Abstract

Objective: To compare the cardiovascular, pulmonary, and ocular hypotensive effects of 0.2% brimonidine tartrate with those of 0.5% timolol maleate, 0.25% betaxolol suspension, and brimonidine vehicle.

Design and patients: A single-center, double-masked, randomized, crossover study of 24 young, healthy men.

Interventions: Baseline heart rate, blood pressure, respiratory rate, and intraocular pressure were recorded at hour 0. At hour 2, heart rate, blood pressure, respiratory rate, and forced expiratory volume in 1 second were measured and a 15-minute treadmill test performed. Hour 0 measurements were repeated at hour 4. On four subsequent visits, we instilled one drop of a study medication into each eye after the baseline measurements at hour 0.

Results: Timolol reduced resting (-5.3 to -6.5 beats/min, P < or = .004) and exercise-induced heart rate (-4.3 to -13.6 beats/min; P < or = .022) compared with brimonidine, betaxolol suspension, and brimonidine vehicle. At hour 4, brimonidine reduced resting systolic blood pressure compared with all other study medications (-5.2 to -7.3 mm Hg; P < or = .024). Timolol reduced systolic blood pressure during exercise and brimonidine reduced systolic blood pressure during recovery more than betaxolol suspension and brimonidine vehicle (-5.1 to -7.7 mm Hg; P < or = .033; and -5.4 to -6.0 mm Hg; P < or = .002, respectively). Mean respiratory rate and forced expiratory volume in 1 second were not significantly altered by any study medication. At hour 4, brimonidine lowered intraocular pressure as well as timolol and better than betaxolol suspension (-1.9 mm Hg; P < .001) or brimonidine vehicle (-1.8 mm Hg; P < .001).

Conclusions: The cardiopulmonary effects of 0.2% brimonidine were limited to a slight reduction in systolic blood pressure during recovery from exercise and at 4 hours after instillation. The ocular hypotensive effect of brimonidine was comparable to that of timolol and greater than that of betaxolol suspension in this patient population.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic alpha-Agonists / administration & dosage
  • Adrenergic alpha-Agonists / pharmacology*
  • Adult
  • Betaxolol / administration & dosage
  • Brimonidine Tartrate
  • Cross-Over Studies
  • Double-Blind Method
  • Exercise Test
  • Hemodynamics / drug effects*
  • Humans
  • Intraocular Pressure / drug effects*
  • Male
  • Middle Aged
  • Ocular Hypotension / chemically induced*
  • Ophthalmic Solutions
  • Quinoxalines / administration & dosage
  • Quinoxalines / pharmacology*
  • Respiration / drug effects*
  • Timolol / administration & dosage

Substances

  • Adrenergic alpha-Agonists
  • Ophthalmic Solutions
  • Quinoxalines
  • Brimonidine Tartrate
  • Timolol
  • Betaxolol