Week 1.07 SCL Care & Solutions

Question 1

Polyhexadine

Answer 1

Antimicrobial activity in low concentrations - belongs to same family of chemicals as chlorhexidine

Question 2

Polyquad

Answer 2

• Has higher molecular weight compared to other preservatives
  o Less diffusion into lens matrix
  o Claimed less allergy or hypersensitivity
  o Some say after 2 hours still similar level of ocular irritation than polyhexadine
• Less potent antimicrobial than polyhexadine hence used at higher conc
  o 0.0001%
  o However, some atopic reactions still occur
• Has good antibacterial/antifungal activity
• Chemically it belongs to the same family as chlorhexidine but is less toxic
• E.g. optifree replenish