The Effects of BAK on the Blood Aqueous Barrier of Pseudophakic Patients
Status:
Completed
Trial end date:
2012-01-01
Target enrollment:
Participant gender:
Summary
BAK is one of the most frequent preservatives in eye drops. BAK is a quaternary ammonium salt
with surfactant qualities. It can be bacteriostatic or bactericidal depending on the
concentrations used. It has been shown to be effective against most bacteria with a few
exceptions, such as Pseudomonas aeruginosa, or picornaviruses. It as been widely used in
eyedrops, nose sprays, hand and face washes, mouthwashes, spermicidal creams, and in various
other cleaners, sanitizers, and disinfectants. BAK gained popularity when it was first
introduced because it also enhances corneal penetration of some drugs by causing epithelial
separation.
It is present in several ophthalmic formulations, including most of the antiglaucoma
medications. If used chronically, BAK has been found to cause ocular surface changes, such as
dry eye and punctuate keratitis. BAK has also been suggested to promote a break in the blood
aqueous barrier, which may lead to undesirable consequences, such as uveitis and cystoid
macular edema. However, this information is controversial. The purpose of this study is to
evaluate the consequences of BAK on the blood-retinal and blood-aqueous barriers of
pseudophakic patients receiving BAK-preserved lubricating drops.