GP lenses do not absorb water like soft lenses. What consequence does this have for contamination and preservative sensitivity?

• A. Because GP lenses are cheaper
• B. Because GP lenses absorb water deeply
• C. Because GP lenses do not absorb water
• D. Because GP lenses are disposable daily

Answer: (C)

GP lenses are non–water-absorbing, rigid lenses. Because they don’t take up water or dissolve substances from tear film, contaminants and preservatives don’t get drawn into the lens material. That means the main risk with contamination is on the lens surface rather than inside the lens itself, so cleaning and surface disinfection are key to removing deposits and microbes. The preservative exposure of the lens material is reduced, since the lens doesn’t absorb aqueous solutions; however, irritation or sensitivity can still occur if preserved solutions remain on the surface or between the lens and cornea, so using appropriate, often preservative-free cleaning/disinfection or rinsing as directed is important for comfort and safety.