The effect of daily use of brimonidine tartrate on the dark-adapted pupil diameter

Am J Ophthalmol. 2004 Jul;138(1):149-51. doi: 10.1016/j.ajo.2004.02.017.


Purpose: To investigate the effect of daily brimonidine tartrate 0.15% on the dark-adapted pupil diameter.

Design: Observational case series.

Method: Ten normal volunteers administered brimonidine to their right eyes once daily. Four to six hours later, infrared pupil photographs were taken after dark adaptation. Measurements were performed at baseline; on treatment days 1, 5, 11, and 18; and on washout days 1 and 2.

Results: One subject had no response. The nine responding subjects showed an average maximum antimydriatic effect of -1.63 mm (range, -0.57 mm--2.30 mm); all subjects experienced tachyphylaxis. Five subjects showed rebound mydriasis (mean maximum rebound +0.87 mm larger than baseline; range 0.50 mm-1.22 mm). The untreated pupil also responded, showing antimydriasis (two subjects), rebound mydriasis (two subjects), or paradoxical direct mydriasis (one subject).

Conclusions: Once-daily use of brimonidine tartrate to prevent dark-induced pupil dilation can lead to tachyphylaxis and rebound mydriasis.

MeSH terms

  • Adolescent
  • Adrenergic alpha-Agonists / administration & dosage*
  • Adult
  • Brimonidine Tartrate
  • Dark Adaptation / drug effects*
  • Humans
  • Mydriasis / etiology
  • Ophthalmic Solutions / administration & dosage
  • Pupil / drug effects*
  • Quinoxalines / administration & dosage*
  • Recurrence
  • Tachyphylaxis


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