Consider concentration and type of preservative in glaucoma medications
DANA POINT, Calif. Preservative agents in glaucoma medications play a role in corneal epithelial damage, said Robert Noecker, MD, here at the Sixth Annual Ocular Drug & Surgical Therapy Update Meeting.
Dr. Noeckers study evaluated the effect of five commonly used glaucoma medications on corneal surface damage and conjunctival inflammation. Each of the glaucoma medications has varying concentrations of benzalkonium chloride (BAK) or Purite (Allergans propreitary preservative).
According to Dr. Noecker, BAK was found to be more toxic than other preservatives, but Purite is converted into natural tear components and has an excellent safety profile.
Corneal epithelial damage is probably multifactorial, related to the concentration of the preservative, the pH of the medication and the drugs mechanism of action, Dr. Noecker said.
Higher BAK concentration appears to be very important but is not the only factor involved in corneal epithelial damage in daily-dosed glaucoma medications, he said.
Glaucoma medications with BAK, when used for 1 month, resulted in inflammatory cell infiltration in the conjunctival epithelium. Medications with the highest levels of BAK produced significantly more inflammation than artificial tears, he said.
The Sixth Annual Ocular Drug & Surgical Therapy Update Meeting is a CME activity sponsored by SLACK Incorporated and supported through an unrestricted grant from Allergan.