Use of benzalkonium chloride-preserved drops may disrupt blood-aqueous barrier

   The short-term use of benzalkonium chloride (BAK)-preserved drops may cause disruption of the blood-aqueous barrier (BAB) in pseudophakic eyes, according to research by Ricardo Abe, MD, of São Paulo, Brazil, and colleagues.  

   They randomized 44 eyes of 44 pseudophakic patients to the use of artificial tears with or without BAK q.i.d. for 30 days. Laser flare meter and OCT measurements of macular thickness were made by a masked observer at baseline and 15 and 30 days after randomization.

    Following data analysis, BAK-preserved artificial tears (n=22) were shown to have resulted in a statistically significant increase in flare measurements on days 15 (P=0.017) and 30 (P=0.043). No change was observed in the group using nonpreserved artificial tears (n=22, P >0.05). No significant differences were found in OCT measurements.   

Dr. Abe and colleagues concluded that short-term use of BAK-preserved drops may cause disruption of the BAB in pseudophakic eyes.